Implant connectors and related methods

ABSTRACT

Implant connectors and related methods are disclosed herein. In some embodiments, a connector can include a low-profile portion to facilitate use of the connector in surgical applications where space is limited. In some embodiments, a connector can include a biased rod-pusher to allow the connector to “snap” onto a rod and/or to “drag” against the rod, e.g., for provisional positioning of the connector prior to locking.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation-in-part of U.S. applicationSer. No. 15/158,127 filed on May 18, 2016, which is hereby incorporatedby reference in its entirety.

FIELD

Implant connectors and related methods are disclosed herein.

BACKGROUND

Fixation systems can be used in orthopedic surgery to maintain a desiredspatial relationship between multiple bones or bone fragments. Forexample, various conditions of the spine, such as fractures,deformities, and degenerative disorders, can be treated by attaching aspinal fixation system to one or more vertebrae. Such systems typicallyinclude a spinal fixation element, such as a rigid or flexible rod orplate, that is coupled to the vertebrae by attaching the element tovarious anchoring devices, such as screws, hooks, or wires. Onceinstalled, the fixation system holds the vertebrae in a desired positionuntil healing or spinal fusion can occur, or for some other period oftime.

There are many instances in which it may be desirable to connectmultiple implants to each other. For example, some revision surgeriesinvolve extending a previously-installed construct to additionalvertebral levels by coupling a newly-installed spinal rod to apreviously-installed rod. By way of further example, aspects of thepatient's anatomy, the surgical technique used, or the desiredcorrection may require that multiple spinal rods be connected to oneanother. As yet another example, coupling multiple rods to one anothercan improve the overall strength and stability of an implantedconstruct.

There can be various difficulties associated with connecting multipleimplants to each other. The available space for the implanted constructcan often be very limited, particularly in the cervical area of thespine. Also, manipulating and handling these relatively small implantsin the surgical wound may be challenging or cumbersome for the surgeon.There is a continual need for improved implant connectors and relatedmethods.

SUMMARY

Implant connectors and related methods are disclosed herein. In someembodiments, a connector can include a low-profile portion to facilitateuse of the connector in surgical applications where space is limited. Insome embodiments, a connector can include a biased rod-pusher to allowthe connector to “snap” onto a rod and/or to “drag” against the rod,e.g., for provisional positioning of the connector prior to locking.

In some embodiments, a connector includes a body that defines first andsecond rod-receiving recesses, the body having proximal and distal endsthat define a proximal-distal axis extending therebetween; a rod pusherslidably disposed within a tunnel formed in the body and configured totranslate with respect to the body along a rod pusher axis; a nutconfigured to translate within a cavity formed in the body along the rodpusher axis; a bias element configured to bias the nut and the rodpusher along the rod pusher axis towards the first rod-receiving recess;a first set screw threadably received in the nut to lock a first rodwithin the first rod-receiving recess; and a second set screw threadablyreceived in the body to lock a second rod within the secondrod-receiving recess.

The nut can be coupled to the rod pusher. The second rod-receivingrecess can be defined by a pair of spaced apart arms of the body. Thenut can include a pair of spaced apart arms aligned with the arms of thebody. The first rod-receiving recess can be open in a distal direction.The second rod-receiving recess can be open in a proximal direction. Therod pusher axis can be substantially perpendicular to theproximal-distal axis. The first rod-receiving recess can be formed in awing portion of the body, the wing portion having a height dimensionextending parallel to a longitudinal axis of the first rod-receivingrecess. The height of the wing portion can be less than about 5 mm. Thefirst rod-receiving recess can be formed in a wing portion of the body,the wing portion having a height dimension extending parallel to alongitudinal axis of the first rod-receiving recess. A ratio of theheight of the wing portion to a diameter of the first rod-receivingrecess can be less than about 2:1. The bias element can include aC-shaped spring clip. The spring clip can be at least partially receivedwithin a groove formed in the cavity of the body and a groove formed inthe nut. The groove formed in the cavity of the body can have a firstend with a smaller radius of curvature and a second end with a largerradius of curvature. A diameter of the first end of the groove can beless than a resting diameter of the spring clip. The connector can havea resting configuration in which the spring clip is disposed in thesecond end of the groove and no rod is disposed in the firstrod-receiving recess. Insertion of a first rod into the firstrod-receiving recess can displace the rod-pusher and the nut along therod pusher axis to move the spring clip towards the first end of thegroove such that the spring clip urges the rod pusher against the firstrod. The bias element can urge the rod pusher against the rod before thefirst set screw is tightened. Tightening the first set screw within thenut can cause a surface of the first set screw to bear against theinterior of a recess formed in the body to urge the nut and the rodpusher towards the first rod-receiving recess and to lock a first rodtherein. A drag force can be exerted on a first rod when the first rodis disposed in the first rod-receiving recess. The connector can providetactile feedback when a first rod is snapped into the firstrod-receiving recess.

In some embodiments, a connector includes a body that defines first andsecond rod-receiving recesses, the body having proximal and distal endsthat define a proximal-distal axis extending therebetween; a firstlocking element configured to lock a first rod within the firstrod-receiving recess, the first locking element being disposed distal tothe second rod-receiving recess; and a second locking element configuredto lock a second rod within the second rod-receiving recess, the secondlocking element being disposed proximal to the second rod-receivingrecess.

The first and second locking elements can be first and second set screwseach having a rotation axis that is parallel to the proximal-distalaxis.

In some embodiments, a method of connecting first and second spinal rodsincludes positioning a first spinal rod within a first rod-receivingrecess formed in a body portion of a connector; tightening a first setscrew within a nut to translate the nut within the body towards thefirst rod-receiving recess and thereby urge a rod pusher against thefirst spinal rod to lock the first spinal rod to the connector;positioning a second spinal rod within a second rod-receiving recessformed in the body portion of the connector; and tightening a second setscrew within the body to lock the second spinal rod to the connector.

The method can include hooking a wing portion of the connector onto thefirst rod at a location between two bone anchors to which the first rodis coupled, the two bone anchors being implanted in adjacent vertebrallevels of a patient's spine. Positioning the first spinal rod within thefirst rod-receiving recess can include displacing the rod pusher awayfrom the first rod-receiving recess and compressing a spring clip into areduced-diameter portion of a groove formed in the body such that therod pusher exerts a drag force on the first rod before the first setscrew is tightened. Tightening the first set screw can includecontacting a ramped surface of the set screw with a corresponding rampedsurface of a recess formed in the body portion of the connector.

In some embodiments, a connector includes a body that defines first andsecond rod-receiving recesses, the body having proximal and distal endsthat define a proximal-distal axis extending therebetween; a rod pusherslidably disposed within a tunnel formed in the body and configured totranslate with respect to the body along a rod pusher axis; a biaselement configured to bias the rod pusher along the rod pusher axistowards the first rod-receiving recess; and a set screw threadablyreceived in the body to lock a first rod within the first rod-receivingrecess and to lock a second rod within the second rod-receiving recess.

The rod pusher can include a first bearing surface configured to contactand bear against a first rod disposed in the first rod-receiving recessand a second bearing surface configured to contact and bear against asecond rod disposed in the second rod-receiving recess. The connectorcan include a saddle disposed in a cavity formed in the body. The saddlecan be translatable along the proximal-distal axis of the body. Thesaddle can include a ramped bearing surface configured to contact andbear against a corresponding ramped bearing surface of the rod pusher.Movement of the saddle along the proximal-distal axis can be effectiveto move the rod pusher along the rod pusher axis. The firstrod-receiving recess can be open in a distal direction. The secondrod-receiving recess can be open in a proximal direction. The rod pusheraxis can be substantially perpendicular to the proximal-distal axis. Thebias element can be received within a through-bore formed in the rodpusher. The bias element can include a spring wire or a leaf springreceived within a through-bore formed in the body and a through-boreformed in the rod pusher. The bias element can include a leaf springreceived within a through-bore formed in the rod pusher and first andsecond recesses formed in the body. The first and second recesses can bedefined by first and second bore holes formed in a distal-facing surfaceof the body. The through-bore in the rod pusher can include acylindrical middle portion and opposed end portions that are elongatedin the direction of the rod pusher axis. The through-bore in the rodpusher can include a reduced-width middle portion and opposed endportions having an increased width, the middle portion being defined atleast in part by a pin inserted through a pin hole that intersects thethrough-bore in the rod pusher. The tunnel can extend between the firstrod-receiving recess and the second rod-receiving recess. The firstrod-receiving recess can be formed in a wing portion of the body, thewing portion having a height dimension extending parallel to alongitudinal axis of the first rod-receiving recess. A ratio of theheight of the wing portion to a diameter of the first rod-receivingrecess can be less than about 2:1. The connector can have a restingconfiguration in which the bias element is in a resting position and norod is disposed in the first rod-receiving recess. Insertion of a rodinto the first rod-receiving recess can displace the rod-pusher alongthe rod pusher axis to bend the bias element away from its restingposition such that the bias element urges the rod pusher against the rodbefore the set screw is tightened. Tightening the set screw within thebody can cause a surface of the set screw to bear against a second roddisposed in the second rod-receiving recess to urge the rod pushertowards the first rod-receiving recess and to lock a first rod in thefirst rod-receiving recess. A drag force can be exerted on a rod whenthe rod is disposed in the first rod-receiving recess. The connector canprovide tactile feedback when a rod is snapped into the firstrod-receiving recess. The second rod-receiving recess can have a reliefdisposed in alignment with the end of the tunnel such that the rodpusher protrudes into the second rod-receiving recess. The secondrod-receiving recess can be asymmetrical about the proximal-distal axis.The second rod-receiving recess can be configured such that, as a rod isseated within the second rod-receiving recess, the rod translatesdistally along the proximal-distal axis and laterally along the rodpusher axis.

In some embodiments, a connector includes a body that defines first andsecond rod-receiving recesses, the body having proximal and distal endsthat define a proximal-distal axis extending therebetween; a rod pusherdisposed within a tunnel formed in the body and configured to rotatewith respect to the body about a pivot axis; and a set screw threadablyreceived in the body to lock a second rod within the secondrod-receiving recess and to thereby pivot the rod pusher to lock a firstrod within the first rod-receiving recess.

In some embodiments, a method of connecting first and second spinal rodsincludes positioning a first spinal rod within a first rod-receivingrecess formed in a body portion of a connector; positioning a secondspinal rod within a second rod-receiving recess formed in the bodyportion of the connector; and tightening a set screw within the body topress the second rod against a rod pusher, thereby urging the rod pusheragainst the first spinal rod to lock the first and second spinal rods tothe connector.

The method can include hooking a wing portion of the connector onto thefirst rod at a location between two bone anchors to which the first rodis coupled, the two bone anchors being implanted in adjacent vertebrallevels of a patient's spine. Tightening the set screw can simultaneouslylock both the first and second rods to the connector.

In some embodiments, a connector includes a body that defines a firstrod-receiving recess, the body having proximal and distal ends thatdefine a proximal-distal axis extending therebetween; a rod pusherdisposed within a tunnel formed in the body, the tunnel extending alonga tunnel axis; a bias element configured to bias the rod pusher towardsthe first rod-receiving recess; and a first set screw threadablyreceived in a proximal end of the tunnel to lock a first rod within thefirst rod-receiving recess.

The bias element can include a leaf spring disposed within athrough-bore formed in the body. A projection of the rod pusher can bereceived within a keyed opening of the leaf spring to retain the rodpusher within the body. The bias element can include a spring wire thatextends through a through-bore formed in the body and a through-boreformed in the rod pusher. The through-bore in the rod pusher can includea cylindrical middle portion and opposed end portions that are elongatedin the direction of the tunnel axis. The rod pusher can be translatablealong the tunnel axis. The tunnel axis can be substantially parallel tothe proximal-distal axis. The rod pusher can be rotatable about a pivotaxis that extends perpendicular to the tunnel axis. The body can definea second rod-receiving recess. The connector can include a second setscrew threadably received in the body to lock a second rod within thesecond rod-receiving recess. The first rod-receiving recess can be openin a lateral direction. The second rod-receiving recess can be open in aproximal direction. The tunnel can extend between the firstrod-receiving recess and a proximal-facing surface of the body portionof the connector. The connector can have a resting configuration inwhich no rod is disposed in the first rod-receiving recess and the biaselement urges the rod pusher distally towards the first rod-receivingrecess. Insertion of a rod into the first rod-receiving recess candisplace the rod-pusher along the tunnel axis to bend the bias elementaway from its resting position such that the bias element urges the rodpusher against the rod before the first set screw is tightened.Tightening the first set screw within the tunnel can cause a surface ofthe set screw to bear against the rod pusher and thereby urge the rodpusher towards the first rod-receiving recess to lock a rod disposedtherein to the connector. A drag force can be exerted on a rod when therod is disposed in the first rod-receiving recess. The connector canprovide tactile feedback when a rod is snapped into the firstrod-receiving recess.

In some embodiments, a method of connecting first and second spinal rodsincludes positioning a first spinal rod within a first rod-receivingrecess formed in a body portion of a connector; and tightening a firstset screw within a tunnel formed in the connector to urge a rod pusherdisposed in the tunnel against the first spinal rod, thereby locking thefirst spinal rod to the connector. A bias element of the connector cancause the rod pusher to exert a drag force on the first rod before thefirst set screw is tightened.

In some embodiments, a connector includes a body that defines first andsecond rod-receiving recesses, the body having proximal and distal endsthat define a proximal-distal axis extending therebetween; a rod pusherslidably disposed within a tunnel formed in the body and configured totranslate with respect to the body along a rod pusher axis; a first setscrew threadably received in the body to translate the rod pusher alongthe rod pusher axis and lock a first rod within the first rod-receivingrecess; and a second set screw threadably received in the body to lock asecond rod within the second rod-receiving recess.

The connector can include a bias element configured to bias the rodpusher along the rod pusher axis towards the first rod-receiving recess.The bias element can be received within a through-bore formed in the rodpusher. The bias element can include a leaf spring received within athrough-bore formed in the rod pusher and first and second recessesformed in the body. The first and second recesses can be defined byfirst and second bore holes formed in a distal-facing surface of thebody. The through-bore in the rod pusher can include a reduced-widthmiddle portion and opposed end portions having an increased width, themiddle portion being defined at least in part by a pin inserted througha pin hole that intersects the through-bore in the rod pusher. The firstrod-receiving recess can be open in a distal direction. The secondrod-receiving recess can be open in a proximal direction. The rod pusheraxis can be substantially perpendicular to the proximal-distal axis. Thefirst rod-receiving recess can be formed in a wing portion of the body,the wing portion having a height dimension extending parallel to alongitudinal axis of the first rod-receiving recess, wherein the heightof the wing portion is less than about 5 mm. The first rod-receivingrecess can be formed in a wing portion of the body, the wing portionhaving a height dimension extending parallel to a longitudinal axis ofthe first rod-receiving recess, wherein a ratio of the height of thewing portion to a diameter of the first rod-receiving recess is lessthan about 2:1. Advancing the first set screw proximally relative to thebody can cause a surface of the first set screw to bear against abearing surface of the rod pusher to urge the rod pusher towards thefirst rod-receiving recess and to lock a first rod therein. A drag forcecan be exerted on a first rod when the first rod is disposed in thefirst rod-receiving recess. The connector can provide tactile feedbackwhen a first rod is snapped into the first rod-receiving recess. Thefirst and second set screws can have a common rotation axis, the commonrotation axis being parallel to the proximal-distal axis. Rotating thefirst set screw in a first direction can move the first set screwproximally to lock a first rod within the first rod-receiving recess androtating the second set screw in the first direction can move the secondset screw distally to lock a second rod within the second rod-receivingrecess. The rod pusher can have a first bearing surface configured tobear against a first rod disposed in the first rod-receiving recess, asecond bearing surface configured to bear against the first set screw,and a third bearing surface configured to bear against a second roddisposed in the second rod-receiving recess.

In some embodiments, a method of connecting first and second spinal rodsincludes positioning a first spinal rod within a first rod-receivingrecess formed in a body portion of a connector; tightening a first setscrew within the body to translate a rod pusher within the body towardsthe first rod-receiving recess and thereby urge the rod pusher againstthe first spinal rod to lock the first spinal rod to the connector;positioning a second spinal rod within a second rod-receiving recessformed in the body portion of the connector; and locking the secondspinal rod to the connector.

Locking the second spinal rod can include tightening a second set screwwithin the body. The method can include hooking a wing portion of theconnector onto the first rod at a location between two bone anchors towhich the first rod is coupled, the two bone anchors being implanted inadjacent vertebral levels of a patient's spine. Positioning the firstspinal rod within the first rod-receiving recess can include displacingthe rod pusher away from the first rod-receiving recess and at least oneof bending, straining, deflecting, and compressing a bias element actingon the rod pusher such that the rod pusher exerts a drag force on thefirst rod before the first set screw is tightened. Tightening the firstset screw can include contacting a ramped surface of the set screw witha corresponding ramped surface of the rod pusher. Locking the second rodcan include forcing the second rod against the rod pusher to force therod pusher against the first rod.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective view of a connector;

FIG. 1B is an exploded perspective view of the connector of FIG. 1Ashown with first and second spinal rods;

FIG. 1C is a perspective view of the connector of FIG. 1A coupled tofirst and second spinal rods;

FIG. 1D is a sectional bottom view of the connector of FIG. 1A and aspinal rod;

FIG. 1E is a sectional side view of the connector of FIG. 1A in a firstconfiguration;

FIG. 1F is a sectional bottom view of the connector of FIG. 1A in thefirst configuration;

FIG. 1G is a sectional side view of the connector of FIG. 1A in a secondconfiguration;

FIG. 1H is a sectional bottom view of the connector of FIG. 1A in thesecond configuration;

FIG. 1I is a sectional side view of the connector of FIG. 1A in a thirdconfiguration;

FIG. 1J is a sectional bottom view of the connector of FIG. 1A in thethird configuration;

FIG. 2A is a perspective view of a connector;

FIG. 2B is an exploded perspective view of the connector of FIG. 2Ashown with first and second spinal rods;

FIG. 2C is a sectional side view of the connector of FIG. 2A in a firstconfiguration;

FIG. 2D is a sectional top view of the connector of FIG. 2A in the firstconfiguration;

FIG. 2E is a sectional side view of the connector of FIG. 2A in a secondconfiguration;

FIG. 2F is a sectional top view of the connector of FIG. 2A in thesecond configuration;

FIG. 2G is a sectional side view of the connector of FIG. 2A in a thirdconfiguration;

FIG. 2H is a sectional top view of the connector of FIG. 2A in the thirdconfiguration;

FIG. 2I is a side view of the connector of FIG. 2A coupled to first andsecond spinal rods;

FIG. 2J is a perspective view of the connector of FIG. 2A shown with asaddle;

FIG. 2K is an exploded perspective view of the connector and saddle ofFIG. 2J shown with first and second spinal rods;

FIG. 2L is a sectional side view of the connector and saddle of FIG. 2Jcoupled to first and second spinal rods;

FIG. 2M is a perspective view of the connector of FIG. 2A shown with apivoting rod pusher;

FIG. 2N is a sectional side view of the connector of FIG. 2M;

FIG. 3A is a perspective view of a connector;

FIG. 3B is an exploded perspective view of the connector of FIG. 3Ashown with first and second spinal rods, with a body of the connectorshown as transparent;

FIG. 3C is a perspective view of the connector of FIG. 3A in a firststate of assembly, with a body of the connector shown as transparent;

FIG. 3D is a perspective view of the connector of FIG. 3A in a secondstate of assembly, with a body of the connector shown as transparent;

FIG. 3E is a perspective view of the connector of FIG. 3A in a thirdstate of assembly, with a body of the connector shown as transparent;

FIG. 3F is a side view of the connector of FIG. 3A in a firstconfiguration, with a body of the connector shown as transparent;

FIG. 3G is a side view of the connector of FIG. 3A in a secondconfiguration, with a body of the connector shown as transparent;

FIG. 3H is a side view of the connector of FIG. 3A in a thirdconfiguration, with a body of the connector shown as transparent;

FIG. 4A is a perspective view of a connector;

FIG. 4B is an exploded perspective view of the connector of FIG. 4Ashown with first and second spinal rods, with a body of the connectorshown as transparent;

FIG. 4C is a sectional perspective view of the connector of FIG. 4Ahaving a spring wire oriented in a first direction, with a body of theconnector shown as transparent;

FIG. 4D is a sectional perspective view of the connector of FIG. 4Ahaving a spring wire oriented in a second direction, with a body of theconnector shown as transparent;

FIG. 4E is a perspective view of the connector of FIG. 4A in a firststate of assembly, with a body of the connector shown as transparent;

FIG. 4F is a perspective view of the connector of FIG. 4A in a secondstate of assembly, with a body of the connector shown as transparent;

FIG. 4G is a perspective view of the connector of FIG. 4A in a thirdstate of assembly, with a body of the connector shown as transparent;

FIG. 4H is a side view of the connector of FIG. 4A in a firstconfiguration, with a body of the connector shown as transparent;

FIG. 4I is a side view of the connector of FIG. 4A in a secondconfiguration, with a body of the connector shown as transparent;

FIG. 4J is a side view of the connector of FIG. 4A in a thirdconfiguration, with a body of the connector shown as transparent;

FIG. 4K is a side view of the connector of FIG. 4A having a pivoting rodpusher, with a body of the connector shown as transparent;

FIG. 5A is a perspective view of a connector;

FIG. 5B is an exploded perspective view of the connector of FIG. 5Ashown with first and second spinal rods;

FIG. 5C is a bottom view of the connector of FIG. 5A;

FIG. 5D is a sectional end view of the connector of FIG. 5A;

FIG. 5E is a sectional side view of the connector of FIG. 5A;

FIG. 5F is a sectional top view of the connector of FIG. 5A;

FIG. 6A is a perspective view of a connector;

FIG. 6B is an exploded perspective view of the connector of FIG. 6Ashown with first and second spinal rods;

FIG. 6C is another perspective view of the connector of FIG. 6A;

FIG. 6D is another perspective view of the connector of FIG. 6A, withthe body of the connector shown as transparent;

FIG. 6E is a sectional side view of the connector of FIG. 6A;

FIG. 6F is a perspective view of the connector of FIG. 6A shown with aspring wire and with the body of the connector shown as transparent; and

FIG. 7 is a perspective view of a human spine with a fixation systemattached thereto.

DETAILED DESCRIPTION

Implant connectors and related methods are disclosed herein. In someembodiments, a connector can include a low-profile portion to facilitateuse of the connector in surgical applications where space is limited. Insome embodiments, a connector can include a biased rod-pusher to allowthe connector to “snap” onto a rod and/or to “drag” against the rod,e.g., for provisional positioning of the connector prior to locking.

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the structure, function,manufacture, and use of the devices and methods disclosed herein. One ormore examples of these embodiments are illustrated in the accompanyingdrawings. Those skilled in the art will understand that the devices andmethods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments. Thefeatures illustrated or described in connection with one exemplaryembodiment may be combined with the features of other embodiments.

FIGS. 1A-1J illustrate an exemplary embodiment of a connector 100. Asshown, the connector 100 can include a body 102 that defines first andsecond rod-receiving recesses 104, 106, a rod pusher 108, a nut 110, abias element or spring clip 112, a first locking element or set screw114, and a second locking element or set screw 116. The nut 110 can beconfigured to translate laterally within the body 102, and can be biasedby the spring clip 112 in a direction that urges the rod pusher 108 intoa first rod R1 disposed in the first rod-receiving recess 104. The firstset screw 114 can be tightened to lock the connector 100 to the firstrod R1. The second set screw 116 can be tightened to lock a second rodR2 in the second rod-receiving recess 106 of the connector 100. Theillustrated connector 100 can thus allow for independent locking offirst and second rods R1, R2 to the connector. The connector 100 caninclude one or more low-profile portions to facilitate use in tightspaces. For example, the first rod-receiving recess 104 can be formed ina portion of the connector body 102 having a reduced-profile, e.g., tofit between bone anchors implanted in adjacent levels of the cervicalspine.

The body 102 can include proximal and distal ends 102 p, 102 d thatdefine a proximal-distal axis A1. The proximal end 102 p of the body 102can include a pair of spaced apart arms 118, 120 that define the secondrod-receiving recess 106 therebetween. A rod R2 disposed in the secondrod-receiving recess 106 can have a central longitudinal rod axis A2.The second rod-receiving recess 106 can be open in a proximal direction,such that a rod R2 can be inserted into the recess by moving the roddistally with respect to the connector 100. Each of the arms 118, 120can extend from the distal portion 102 d of the body 102 to a free end.The outer surfaces of each of the arms 118, 120 can include a feature(not shown), such as a recess, dimple, notch, projection, or the like,to facilitate coupling of the connector 100 to various instruments. Forexample, the outer surface of each arm 118, 120 can include an arcuategroove at the respective free end of the arms for attaching theconnector 100 to an extension tower or retractor. The arms 118, 120 caninclude or can be coupled to extension or reduction tabs (not shown)that extend proximally from the body 102 to functionally extend thelength of the arms 118, 120. The extension tabs can facilitate insertionand reduction of a rod or other implant, as well as insertion andlocking of the set screw 116. The extension tabs can be configured tobreak away or otherwise be separated from the arms 118, 120. The innersurfaces of each of the arms 118, 120 can be configured to mate with thesecond set screw 116. For example, the inner surfaces of the arms 118,120 can include threads that correspond to external threads formed onthe second set screw 116. Accordingly, rotation of the second set screw116 with respect to the body 102 about the axis A1 can be effective totranslate the set screw with respect to the body axially along the axisA1.

The distal end 102 d of the body 102 can define an interior cavity 122in which the nut 110 can be disposed. At least one dimension of thecavity 122 can be greater than a corresponding dimension of the nut 110to allow the nut to translate within the cavity along a rod pusher axisA3. The axis A3 can be perpendicular or substantially perpendicular tothe axis A1. The axis A3 can also be perpendicular or substantiallyperpendicular to the axis A2. The axis A3 can extend from the axis A1 atan angle in the range of about 60 degrees to about 120 degrees. In theillustrated embodiment, the cavity 122 has an oval-shaped cross section.An undercut groove 124 can be formed in the cavity 122 to receive atleast a portion of the spring clip 112. As shown in FIG. 1D, the crosssection of the groove 124 can be substantially elliptical with differentsized curvatures at each end of the major axis of the ellipse. A firstend 124A of the groove 124 can have a relatively smaller radius ofcurvature and a second, opposite end 124B of the groove 124 can have arelatively larger radius of curvature. Curved transition portions of thegroove 124 can extend between the first and second ends 124A, 124B, suchthat the groove is generally egg-shaped in cross section. The diameterof the first end 124A of the groove can be less than the restingdiameter of the spring clip 112, such that the spring clip's tendency toexpand towards its resting diameter urges the spring clip and, byextension, the nut 110 and the rod pusher 108, along the axis A3 towardsthe first rod-receiving recess 104. The diameter of the second end 124Bof the groove 124 can be greater than, equal to, or slightly less thanthe resting diameter of the spring clip 112.

A recess 126 sized to receive at least a portion of the first set screw114 can be formed in the body 102, as shown for example in FIG. 1E. Therecess 126 can be formed distal to the cavity 122. The recess 126 can befrustoconical as shown to provide a ramped bearing surface forengagement with the distal end of the first set screw 114. In otherembodiments, the recess 126 can be cylindrical or can have other shapes.

A tunnel 128 can be formed in the body 102 and can extend along the axisA3 between the cavity 122 and the first rod-receiving recess 104. Thetunnel 128 can have a shape that is substantially a negative of theexterior shape of the rod pusher 108. The rod pusher 108 can be slidablydisposed within the tunnel 128 such that the rod pusher can translatealong the axis A3 with respect to the body 102.

The body 102 can include a cantilevered wing portion 130 that definesthe first rod-receiving recess 104. A rod R1 disposed in the firstrod-receiving recess 104 can have a central longitudinal rod axis A4.The axis A4 can be parallel to the axis A2 as shown, or can beperpendicular or obliquely angled with respect to the axis A2. The wingportion 130 can extend radially-outward from the second arm 120 of thebody 102. The wing portion 130 can have a width 130W and a height 130H.A ratio of the width 130W to the diameter of the first rod-receivingrecess 104 (or of a rod R1 disposed therein) can be less than about1.5:1, less than about 2:1, and/or less than about 3:1. A ratio of theheight 130H to the diameter of the first rod-receiving recess 104 (or ofa rod R1 disposed therein) can be less than about 0.5:1, less than about1:1, and/or less than about 2:1. In some embodiments, the height 130Hcan be less than about 5 mm, less than about 4 mm, and/or less thanabout 3 mm. The first rod-receiving recess 104 can be open in a distaldirection such that a rod R1 can be inserted into the recess by movingthe connector 100 distally with respect to the rod. In otherembodiments, the first rod-receiving recess 104 can be open in aproximal direction, e.g., by flipping the wing portion 130 and formingit such that it extends from a distal portion of the body 102, or openin a lateral direction.

The nut 110 can be positioned within the cavity 122 formed in the body102. The nut 110 can be sized such that it is laterally translatablewithin the cavity 122, along the axis A3. The nut 110 can be generallycylindrical with first and second arms 132, 134 extending in a proximaldirection to respective free ends of the arms. The first and second arms132, 134 can be aligned with the first and second arms 118, 120 of thebody 102 such that a recess defined therebetween is aligned with thesecond rod-receiving recess 106. Accordingly, the second rod R2 can besimultaneously cradled between the arms 132, 134 of the nut 110 and thearms 118, 120 of the body 102 when the rod is disposed in the secondrod-receiving recess 106.

The nut 110 can include a mating feature configured to couple the nut tothe rod pusher 108. For example, the nut can include a dovetail groove136 formed in an exterior surface thereof sized to receive acorresponding dovetail projection 138 formed on the rod pusher 108. Themating feature can be configured to prevent movement of the rod pusher108 with respect to the nut 110 along the axis A3, while still allowingmovement of the rod pusher with respect to the nut along the axis A1.Accordingly, the nut 110 can be assembled to the rod pusher 108 and thebody 102 by inserting the rod pusher through the tunnel 128 along theaxis A3 such that the dovetail projection 138 extends into the cavity122 of the body 102, and then lowering the nut distally into the cavityalong the axis A1, with the projection 138 of the rod pusher 108 slidinginto the groove 136 of the nut as the nut is advanced into the cavity.It will be appreciated that the groove can alternatively be formed inthe rod pusher 108 and the projection formed on the nut 110. It willfurther be appreciated that the nut 110 can be formed integrally withthe rod pusher 108, or mated to the rod pusher in other ways.

The nut 110 can include an annular groove 140 formed in an exteriorsurface thereof sized to receive at least a portion of the spring clip112. When the connector 100 is assembled, the spring clip 112 can extendpartially into the groove 124 formed in the cavity 122 and partiallyinto the groove 140 formed in the nut 110 to retain the nut within thecavity.

The nut 110 can define a central opening 142 that extends completelythrough the nut along the axis A1. The inner surface of the opening 142can be configured to mate with the first set screw 114. For example, theinner surface 142 can include threads that correspond to externalthreads formed on the first set screw 114. Accordingly, rotation of thefirst set screw 114 with respect to the nut 110 about the axis A1 can beeffective to translate the set screw with respect to the nut axiallyalong the axis A1.

As noted above, the rod pusher 108 can be slidably disposed within thetunnel 128 of the body 102 and can be configured to translate withrespect to the body along the axis A3. The rod pusher 108 can include abearing surface 144 configured to contact and bear against a rod R1disposed in the first rod-receiving recess 104. The bearing surface 144can extend at an oblique angle with respect to a longitudinal axis ofthe rod pusher 108 such that the bearing surface is ramped. The bearingsurface 144 can be planar as shown, or can be convex, concave, pointed,sharpened, etc. For example, the bearing surface 144 can be concave andcan define a section of a cylinder, such that the bearing surfacematches or approximates the contour of a cylindrical rod R1 disposed inthe first rod-receiving recess 104. The rod pusher 108 can include aprojection 138 or other mating feature, as described above, for matingthe rod pusher to the nut 110.

The bias element can be configured to bias the nut 110 and the rodpusher 108 towards the first rod-receiving recess 104. In theillustrated embodiment, the bias element is a C-shaped spring clip 112.The spring clip 112 can be formed from a resilient material such that,when radially-compressed, the spring clip tends to expandradially-outward towards its resting diameter. Accordingly, whencompressed into the groove 124 formed in the cavity 122, the spring clip112 can exert a radial-outward force against the walls of the groove andcan tend to urge the nut 110 and the rod pusher 108 towards the firstrod-receiving recess 104. While a C-shaped spring clip 112 is shown,various other bias elements can be used instead or in addition, such asleaf springs, wire springs, wave springs, coil springs, and the like.

The first set screw 114 can include a proximal portion 114 p and adistal portion 114 d. The proximal portion 114 p of the first set screw114 can include an exterior thread configured to mate with the interiorthreads of the nut 110 to allow the first set screw to be advanced orretracted along the axis A1 with respect to the nut by rotating thefirst set screw about the axis A1. The proximal portion 114 p of thefirst set screw 114 can include a driving interface 146 configured toreceive a driver for applying a rotational force to the first set screwabout the axis A1. The distal portion 114 d of the first set screw 114can define a bearing surface configured to contact and bear against therecess 126 formed in the body 102. In the illustrated embodiment, thedistal portion 114 d of the first set screw 114 defines a frustoconicalramped bearing surface that corresponds to the ramped bearing surface ofthe recess 126. While a first set screw 114 is shown, it will beappreciated that other locking elements can be used instead or addition,such as a closure cap that advances and locks by quarter-turn rotation,a closure cap that slides in laterally without rotating, and so forth.

The second set screw 116 can include an exterior thread configured tomate with the interior threads formed on the arms 118, 120 of the body102 to allow the second set screw to be advanced or retracted along theaxis A1 with respect to the body by rotating the second set screw aboutthe axis A1. The second set screw 116 can include a driving interface148 configured to receive a driver for applying a rotational force tothe second set screw about the axis A1. The distal surface of the secondset screw 116 can be configured to contact and bear against a rod R2disposed in the second rod-receiving 106 recess to lock the rod to theconnector 100. When tightened against the rod R2, the second set screw116 can prevent the rod from translating relative to the connector 100along the axis A2 and/or from rotating with respect to the connectorabout the axis A2. While a second set screw 116 is shown, it will beappreciated that other locking elements can be used instead or addition,such as a closure cap that advances and locks by quarter-turn rotation,a closure cap that slides in laterally without rotating, a nut thatthreads onto an exterior of the connector 100, and so forth.

Operation of the connector 100 is illustrated schematically in FIGS.1E-1J.

As shown in FIGS. 1E-1F, the connector 100 can have a restingconfiguration in which no rod is disposed in the first or secondrod-receiving recesses 104, 106. In this configuration, the biasingforce of the spring clip 112 can cause the spring clip to slide into thelarger diameter portion 124B of the groove 124, thereby sliding the nut110 and the rod pusher 108 towards the first rod-receiving recess 104.The first set screw 114 can be mounted in the nut 110 at this time, butnot advanced far enough for the distal end 114 d of the set screw tocontact the recess 126 of the body 102.

In the resting configuration, the wing portion 130 of the body 102 andthe free end of the rod pusher 108 can define an aperture 150 that issmaller than the diameter of a first rod R1 to which the connector 100is to be coupled. Accordingly, as shown in FIGS. 1G-1H, as the rod R1 isinserted into the first rod-receiving recess 104, the rod bears againstthe rod pusher 108 to move the connector 100 out of the restingconfiguration. Insertion of the rod R1 can move the rod pusher 108 andthe nut 110 along the axis A3, thereby compressing the spring clip 112towards the smaller diameter portion 124A of the groove 124. As thelargest cross-sectional portion of the rod R1 is positioned in theaperture 150, the nut 110 can be displaced to its furthest distance fromthe first rod-receiving recess 104.

As shown in FIGS. 1I-1J, once the largest cross-sectional portion of therod R1 clears the aperture 150 as the rod is seated in the firstrod-receiving recess 104, the biasing force of the spring clip 112 cancause the nut 110 and the rod pusher 108 to move back along the axis A3towards the first rod-receiving recess. This movement can at leastpartially close the aperture 150 around the rod R1 to capture the rod inthe first rod-receiving recess 104. The biasing force of the spring clip112 can resist retrograde movement of the rod pusher 108 and thus resistdisconnection of the connector 100 from the first rod R1. The springclip 112 can be at least partially compressed when the rod R1 is fullyseated in the recess 104, such that the rod pusher 108 exerts acontinuous drag force on the rod R1. When the connector 100 ispositioned as desired with respect to the first rod R1, the first setscrew 114 can be tightened within the nut 110 to lock the rod in thefirst rod-receiving recess 104. As the first set screw 114 is tightened,the ramped surface of the first set screw can bear against the rampedsurface of the recess 126 to urge the nut 110 towards the firstrod-receiving recess 104 and urge the rod pusher 108 firmly into contactwith the rod R1. When the first set screw 114 is tightened, theconnector 100 can be locked to the first rod R1 to resist or preventtranslation of the rod R1 with respect to the connector along the axisA4 and to resist or prevent rotation of the rod R1 with respect to theconnector about the axis A4. A second rod R2 can be positioned in thesecond rod-receiving recess 106 and the second set screw 116 can betightened to lock the rod R2 to the body 102.

The connector 100 can thus be used to connect a first spinal rod R1 to asecond spinal rod R2. While use of the connector 100 with first andsecond spinal rods is generally described herein, it will be appreciatedthat the connector can instead be configured for use with other types oforthopedic hardware, whether implanted or external. For example, one orboth halves of the connector 100 can be modified to couple other variouscomponents to each other (e.g., to couple a rod to a plate, to couple aplate to a plate, to couple a rod to cable, to couple a cable to acable, and so forth).

The connector 100 can provide various benefits for the user and/orpatient. For example, the biased rod pusher 108 can provide tactilefeedback when the connector 100 is “snapped” onto the first rod R1,giving the user confidence that the rod has been attached successfullybefore tightening the connector 100. The biased rod pusher 108 can alsoapply friction or “drag” to the rod R1 prior to locking the set screws114, 116, helping to keep the connector 100 in place and prevent“flopping” while still allowing free movement when intended by the user.By way of further example, the low-profile geometry of the wing portion130 of the connector 100 can allow the connector to be used in surgicalareas where space is limited (e.g., in the cervical area of the spine).In an exemplary method, the wing portion 130 of the connector 100 can behooked onto a first rod R1 at a location between two bone anchors towhich the rod is coupled, the two bone anchors being implanted inadjacent vertebral levels of the cervical spine. As yet another example,the connector 100 can facilitate independent locking of the first andsecond rods R1, R2. This can allow the connector 100 to be locked to thefirst rod R1 to limit or prevent movement of the connector before thesecond rod R2 is attached and/or locked.

FIGS. 2A-2N illustrate an exemplary embodiment of a connector 200. Asshown, the connector 200 can include a body 202 that defines first andsecond rod-receiving recesses 204, 206, a rod pusher 208, a bias elementor spring wire 212, and a locking element or set screw 216. The rodpusher 208 can be configured to translate laterally within the body 202,and can be biased by the spring wire 212 in a direction that urges therod pusher into a first rod R1 disposed in the first rod-receivingrecess 204. The set screw 216 can be tightened to lock the connector 200to both the first rod R1 and to a second rod R2 disposed in the secondrod-receiving recess 206. The illustrated connector 200 can thus allowfor one-step locking of first and second rods R1, R2 to the connector.The connector 200 can include one or more low-profile portions tofacilitate use in tight spaces. For example, the first rod-receivingrecess 204 can be formed in a portion of the connector body 202 having areduced-profile, e.g., to fit between bone anchors implanted in adjacentlevels of the cervical spine.

The body 202 can include proximal and distal ends 202 p, 202 d thatdefine a proximal-distal axis A1. The proximal end 202 p of the body 202can include a pair of spaced apart arms 218, 220 that define the secondrod-receiving recess 206 therebetween. A rod R2 disposed in the secondrod-receiving recess 206 can have a central longitudinal rod axis A2.The second rod-receiving recess 206 can be open in a proximal direction,such that a rod R2 can be inserted into the recess by moving the roddistally with respect to the connector 200. Each of the arms 218, 220can extend from the distal portion 202 d of the body 202 to a free end.The outer surfaces of each of the arms 218, 220 can include a feature(not shown), such as a recess, dimple, notch, projection, or the like,to facilitate coupling of the connector 200 to various instruments. Forexample, the outer surface of each arm 218, 220 can include an arcuategroove at the respective free end of the arms for attaching theconnector 200 to an extension tower or retractor. The arms 218, 220 caninclude or can be coupled to extension or reduction tabs (not shown)that extend proximally from the body 202 to functionally extend thelength of the arms 218, 220. The extension tabs can facilitate insertionand reduction of a rod or other implant, as well as insertion andlocking of the set screw 216. The extension tabs can be configured tobreak away or otherwise be separated from the arms 218, 220. The innersurfaces of each of the arms 218, 220 can be configured to mate with theset screw 216. For example, the inner surfaces of the arms 218, 220 caninclude threads that correspond to external threads formed on the setscrew 216. Accordingly, rotation of the set screw 216 with respect tothe body 202 about the axis A1 can be effective to translate the setscrew with respect to the body axially along the axis A1.

The distal end 202 d of the body 202 can define a tunnel 228 in whichthe rod pusher 208 can be disposed. The tunnel 228 can extend along arod pusher axis A3 between the second rod-receiving recess 206 and thefirst rod-receiving recess 204. The rod pusher 208 can be configured totranslate within the tunnel 228 along the axis A3. The axis A3 can beperpendicular or substantially perpendicular to the axis A1. The axis A3can also be perpendicular or substantially perpendicular to the axis A2.The axis A3 can extend from the axis A1 at an angle in the range ofabout 60 degrees to about 120 degrees. The tunnel 228 can have a shapethat is substantially a negative of the exterior shape of the rod pusher208. A through-bore 224 can be formed in the body 202 such that thethrough-bore intersects with the tunnel 228. The through-bore 224 canextend perpendicular or substantially perpendicular to the axis A3. Thethrough-bore 224 can be sized to receive the spring wire 212 therein, asdescribed further below. The through-bore 224 can be open at both endsor one or both ends can be closed.

The body 202 can include a cantilevered wing portion 230 that definesthe first rod-receiving recess 204. A rod R1 disposed in the firstrod-receiving recess 204 can have a central longitudinal rod axis A4.The axis A4 can be parallel to the axis A2 as shown, or can beperpendicular or obliquely angled with respect to the axis A2. The wingportion 230 can extend radially-outward from the second arm 220 of thebody 202. The wing portion 230 can have a width 230W and a height 230H.A ratio of the width 230W to the diameter of the first rod-receivingrecess 204 (or of a rod R1 disposed therein) can be less than about1.5:1, less than about 2:1, and/or less than about 3:1. A ratio of theheight 230H to the diameter of the first rod-receiving recess 204 (or ofa rod R1 disposed therein) can be less than about 0.5:1, less than about1:1, and/or less than about 2:1. In some embodiments, the height 230Hcan be less than about 5 mm, less than about 4 mm, and/or less thanabout 3 mm. The first rod-receiving recess 204 can be open in a distaldirection such that a rod R1 can be inserted into the recess by movingthe connector 200 distally with respect to the rod. In otherembodiments, the first rod-receiving recess 204 can be open in aproximal direction, e.g., by flipping the wing portion 230 and formingit such that it extends from a distal portion of the body 202, or in alateral direction.

As noted above, the rod pusher 208 can be slidably disposed within thetunnel 228 of the body 202 and can be configured to translate withrespect to the body along the axis A3. The rod pusher 208 can include afirst bearing surface 244A configured to contact and bear against afirst rod R1 disposed in the first rod-receiving recess 204. The bearingsurface 244A can extend at an oblique angle with respect to alongitudinal axis of the rod pusher 208 such that the bearing surface isramped. The bearing surface 244A can be planar as shown, or can beconvex, concave, pointed, sharpened, etc. For example, the bearingsurface 244A can be concave and can define a section of a cylinder, suchthat the bearing surface matches or approximates the contour of acylindrical rod R1 disposed in the first rod-receiving recess 204. Therod pusher 208 can include a second bearing surface 244B configured tocontact and bear against a second rod R2 disposed in the secondrod-receiving recess 206. The bearing surface 244B can extend at anoblique angle with respect to a longitudinal axis of the rod pusher 208such that the bearing surface is ramped. The bearing surface 244B can beplanar as shown, or can be convex, concave, pointed, sharpened, etc. Forexample, the bearing surface 244B can be concave and can define asection of a cylinder, such that the bearing surface matches orapproximates the contour of a cylindrical rod R2 disposed in the secondrod-receiving recess 206.

The rod pusher 208 can include a through bore 226. The through-bore 226can extend perpendicular or substantially perpendicular to the axis A3.The through-bore 226 can be sized to receive the spring wire 212therein. In at least some positions of the rod pusher 208 with respectto the body 202, the through-bore 226 of the rod pusher can be alignedwith the through-bore 224 of the body, such that the spring wire 212extends through both through-bores 224, 226. As best shown in FIGS. 2D,2F, and 2H, the through-bore 226 can include a middle portion andopposed end portions. The middle portion of the through-bore 226 canapproximate the dimensions of the spring wire 212. For example, themiddle portion can be cylindrical and can have a diameter that issubstantially equal to the diameter of the spring wire 212. The endportions of the through-bore 226 can be elongated or can otherwise havea dimension greater than the diameter of the spring wire 212 to allowthe rod pusher 208 to translate along the axis A3 and to accommodate thebend radius of the spring wire 212 during such translation. In someembodiments, the middle portion of the through-bore 226 can be definedby a pin inserted through the rod pusher 208, as described further belowwith respect to FIG. 5F.

The bias element can be configured to bias the rod pusher 208 towardsthe first rod-receiving recess 204. In the illustrated embodiment, thebias element is a cylindrical spring wire 212. The spring wire 212 canbe formed from a resilient material such that, when deformed from astraight line, the spring wire tends to flex back towards its straightresting configuration. Accordingly, when deformed by movement of the rodpusher 208, the spring wire 212 can exert a force against the interiorof the through-bore 226 to urge the rod pusher 208 towards the firstrod-receiving recess 204. While a straight, cylindrical spring wire 212is shown, various other bias elements can be used instead or inaddition, such as non-straight or non-cylindrical wires, leaf springs,spring clips, wave springs, coil springs, and the like. In someembodiments, the bias element can be omitted. For example, the rodpusher 208 can be free to float within the tunnel 228, or can beretained by a pin or other retention feature without being biasedtowards the first rod-receiving recess 204.

The set screw 216 can include an exterior thread configured to mate withthe interior threads formed on the arms 218, 220 of the body 202 toallow the set screw to be advanced or retracted along the axis A1 withrespect to the body by rotating the set screw about the axis A1. The setscrew 216 can include a driving interface 248 configured to receive adriver for applying a rotational force to the set screw about the axisA1. The distal surface of the set screw 216 can be configured to contactand bear against a rod R2 disposed in the second rod-receiving 206recess to lock the rod to the connector 200. When tightened against therod R2, the set screw 216 can prevent the rod from translating relativeto the connector 200 along the axis A2 and/or from rotating with respectto the connector about the axis A2. While a set screw 216 is shown, itwill be appreciated that other locking elements can be used instead oraddition, such as a closure cap that advances and locks by quarter-turnrotation, a closure cap that slides in laterally without rotating, a nutthat threads onto an exterior of the connector 200, and so forth.

Operation of the connector 200 is illustrated schematically in FIGS.2C-2H.

As shown in FIGS. 2C-2D, the connector 200 can have a restingconfiguration in which no rod is disposed in the first or secondrod-receiving recesses 204, 206. In this configuration, the biasingforce of the spring wire 212 can cause the rod pusher 208 to slidetowards the first rod-receiving recess 204.

In the resting configuration, the wing portion 230 of the body 202 andthe free end of the rod pusher 208 can define an aperture 250 that issmaller than the diameter of a first rod R1 to which the connector 200is to be coupled. Accordingly, as shown in FIGS. 2E-2F, as the rod R1 isinserted into the first rod-receiving recess 204, the rod bears againstthe rod pusher 208 to move the connector 200 out of the restingconfiguration. Insertion of the rod R1 can move the rod pusher 208 alongthe axis A3, thereby deforming the spring wire 212 from its restingstate. As the largest cross-sectional portion of the rod R1 ispositioned in the aperture 250, the rod pusher 208 can be displaced toits furthest distance from the first rod-receiving recess 204.

As shown in FIGS. 2G-2H, once the largest cross-sectional portion of therod R1 clears the aperture 250 as the rod is seated in the firstrod-receiving recess 204, the biasing force of the spring wire 212 cancause the rod pusher 208 to move back along the axis A3 towards thefirst rod-receiving recess. This movement can at least partially closethe aperture 250 around the rod R1 to capture the rod in the firstrod-receiving recess 204. The biasing force of the spring wire 212 canresist retrograde movement of the rod pusher 208 and thus resistdisconnection of the connector 200 from the first rod R1. The geometryof the connector 200 can be selected such that, when the rod R1 is fullyseated in the first rod-receiving recess 204, the spring wire 212 isdeformed from its resting state. The spring wire 212 can thus press therod pusher 208 against the rod R1 to provide a friction or drag effect,before the set screw 216 is tightened and/or before a second rod R2 ispositioned in the connector 200.

A second rod R2 can be positioned in the second rod-receiving recess206, and the set screw 216 can be tightened to lock the connector 200 tothe first and second rods R1, R2. As the set screw 216 is tightened, thesecond rod R2 can press against the second bearing surface 244B of therod pusher 208, urging the rod pusher towards the first rod-receivingrecess 204 and firmly into contact with the rod R1. When the set screw216 is tightened, the connector 200 can be locked to the first andsecond rods R1, R2 to resist or prevent translation of the rods R1, R2with respect to the connector along the axes A2, A4 and to resist orprevent rotation of the rods R1, R2 with respect to the connector aboutthe axes A2, A4.

As shown in FIG. 2I, the second rod-receiving recess 206 can be shapedto encourage contact between the second rod R2 and the second bearingsurface 244B of the rod pusher 208. In other words, the recess 206 canbe shaped to reduce or eliminate the risk that the second rod R2 willonly bear against the floor of the recess 206 when the set screw 216 istightened, without applying sufficient force to the bearing surface244B. As shown, the recess 206 can include a relief disposed inalignment with the end of the tunnel 228 such that the rod pusher 208protrudes into the recess. The recess 206 can thus be asymmetrical aboutthe axis A1, and can deviate from a symmetrical U-shape. When the rod R2is bottomed out in the recess 206, the central longitudinal axis A2 ofthe rod can be offset from the axis A1. The central longitudinal axis ofthe rod R2 when the rod is fully seated is shown in FIG. 2I as axis A5.The recess 206 can be configured such that, as the rod R2 is seatedwithin the recess 206, it translates distally along the axis A1 andlaterally along the axis A3.

As shown in FIGS. 2J-2L, the connector 200 can include a saddle 210. Thesaddle 210 can be included in addition to the asymmetrical recess 206 oras an alternative thereto. The saddle 210 can be positioned within acavity 222 formed in the body 202. The saddle 210 can be generallycylindrical with first and second arms 232, 234 extending in a proximaldirection to respective free ends of the arms. The first and second arms232, 234 can be aligned with the first and second arms 218, 220 of thebody 202 such that a recess defined therebetween is aligned with thesecond rod-receiving recess 206. Accordingly, the second rod R2 can besimultaneously cradled between the arms 232, 234 of the saddle 210 andthe arms 218, 220 of the body 202 when the rod is disposed in the secondrod-receiving recess 206. The saddle 210 can include a ramped bearingsurface 240 configured to contact and bear against the second bearingsurface 244B of the rod pusher 208. The bearing surface 240 can extendat an oblique angle with respect to the axis A1. The bearing surface 240can be planar as shown, or can be convex, concave, pointed, sharpened,etc. In operation, a force applied to the saddle 210 along the directionA1, e.g., by tightening the set screw 216 down onto the saddle or downonto a rod R2 disposed in the saddle, can cause the saddle 210 totranslate distally with respect to the body 202 and cause the bearingsurface 240 to ramp along the bearing surface 244B of the rod pusher208, urging the rod pusher towards the first rod-receiving recess 204along the axis A3. Accordingly, tightening the set screw 216 can beeffective to simultaneously lock both rods R1, R2 to the connector 200.The saddle 210 can allow for locking of rods having different diametersin the second rod-receiving recess 206, while still ensuring that,regardless of the diameter of the second rod R2, sufficient force isapplied to the rod pusher 208 to lock the first rod R1.

As shown in FIGS. 2M-2N, the rod pusher 208 can be configured to pivotwith respect to the body 202, instead of translating relative to thebody or in addition to translating relative to the body. The tunnel 228can be oversized or can include one or more reliefs 256 formed thereinto allow the rod pusher 208 to rotate within the tunnel about a pivotaxis A8. The rod pusher 208 can be pivotally mounted within the tunnel228 by a pivot pin 254. The connector 200 can include a bias element tobias the rod pusher 208. For example, a spring wire of the typedescribed above can be used to bias translation of the rod pusher 208relative to the body 202. By way of further example, the pivot pin 254can be a torsion bar that biases rotation of the rod pusher 208 relativeto the body 202. Other ways of biasing rotation of the rod pusher 208can be used instead or in addition, such as coil springs, leaf springs,and the like. In operation, a force applied to a first end of the rodpusher 208 along the direction A1, e.g., by tightening the set screw 216down onto a rod R2 disposed in the second recess 206, can cause the rodpusher to pivot or rotate about the pivot axis A8, urging a secondopposite end of the rod pusher against a rod R1 disposed in the firstrecess 204. Accordingly, tightening the set screw 216 can be effectiveto simultaneously lock both rods R1, R2 to the connector 200. Theconnector of FIGS. 2M-2N can provide a mechanical advantage in lockingthe first rod R1 due to the lever action of the pivoting rod pusher 208.

In some embodiments, the arms 232, 234 can extend proximally past themaximum dimension of the rod R2 and the set screw 216 can include anouter screw configured to bear against a proximal-facing surface of thearms. An inner set screw can be threadably mounted within the outer setscrew. Accordingly, the outer set screw can be tightened first to pressdown on the saddle 210 and lock the first rod R1 in the firstrod-receiving recess 204. Then, the inner set screw can be tightened topress down on the second rod R2 and lock the second rod in the secondrod-receiving recess 206. The dual set screw can thus facilitateindependent locking of the first and second rods R1, R2 to the connector200. While not shown in FIGS. 2J-2L, embodiments of the connector 200that include a saddle 210 can also include a bias element as describedabove for biasing the rod pusher 208 towards the first rod-receivingrecess 204.

The connector 200 can thus be used to connect a first spinal rod R1 to asecond spinal rod R2. While use of the connector 200 with first andsecond spinal rods is generally described herein, it will be appreciatedthat the connector can instead be configured for use with other types oforthopedic hardware, whether implanted or external. For example, one orboth halves of the connector 200 can be modified to couple other variouscomponents to each other (e.g., to couple a rod to a plate, to couple aplate to a plate, to couple a rod to cable, to couple a cable to acable, and so forth).

The connector 200 can provide various benefits for the user and/orpatient. For example, the biased rod pusher 208 can provide tactilefeedback when the connector 200 is “snapped” onto the first rod R1,giving the user confidence that the rod has been attached successfullybefore tightening the connector. The biased rod pusher 208 can alsoapply friction or “drag” to the rod R1 prior to locking the set screw216, helping to keep the connector in place and prevent “flopping” whilestill allowing free movement when intended by the user. By way offurther example, the low-profile geometry of the wing portion 230 of theconnector 200 can allow the connector to be used in surgical areas wherespace is limited (e.g., in the cervical area of the spine). In anexemplary method, the wing portion 230 of the connector 200 can behooked onto a first rod R1 at a location between two bone anchors towhich the rod is coupled, the two bone anchors being implanted inadjacent vertebral levels of the cervical spine. As yet another example,the connector 200 can facilitate simultaneous and/or single-step lockingof the first and second rods R1, R2. This can allow the connector 200 tobe locked to both rods R1, R2 with minimal steps. In other embodiments,the connector 200 can facilitate independent locking of the rods R1, R2,e.g., with use of a saddle 210 and dual set screw.

FIGS. 3A-3H illustrate an exemplary embodiment of a connector 300. Asshown, the connector 300 can include a body 302 that defines first andsecond rod-receiving recesses 304, 306, a rod pusher 308, a bias elementor leaf spring 312, a first locking element or set screw 314, and asecond locking element or set screw 316. The rod pusher 308 can bebiased by the leaf spring 312 in a direction that urges the rod pusherinto a first rod R1 disposed in the first rod-receiving recess 304. Thefirst set screw 314 can be tightened to lock the connector 300 to thefirst rod R1. The second set screw 316 can be tightened to lock a secondrod R2 in the second rod-receiving recess 306 of the connector 300. Theillustrated connector 300 can thus allow for independent locking offirst and second rods R1, R2 to the connector. The connector 300 caninclude one or more low-profile portions to facilitate use in tightspaces. For example, the first rod-receiving recess 304 can be formed ina portion of the connector body 302 having a reduced-profile, e.g., tofit between bone anchors implanted in adjacent levels of the cervicalspine.

The body 302 can include proximal and distal ends 302 p, 302 d thatdefine a proximal-distal axis A1. The proximal end 302 p of the body 302can include a pair of spaced apart arms 318, 320 that define the secondrod-receiving recess 306 therebetween. A rod R2 disposed in the secondrod-receiving recess 306 can have a central longitudinal rod axis A2.The second rod-receiving recess 306 can be open in a proximal direction,such that a rod R2 can be inserted into the recess by moving the roddistally with respect to the connector 300. Each of the arms 318, 320can extend from the distal portion 302 d of the body 302 to a free end.The outer surfaces of each of the arms 318, 320 can include a feature(not shown), such as a recess, dimple, notch, projection, or the like,to facilitate coupling of the connector 300 to various instruments. Forexample, the outer surface of each arm 318, 320 can include an arcuategroove at the respective free end of the arms for attaching theconnector 300 to an extension tower or retractor. The arms 318, 320 caninclude or can be coupled to extension or reduction tabs (not shown)that extend proximally from the body 302 to functionally extend thelength of the arms 318, 320. The extension tabs can facilitate insertionand reduction of a rod or other implant, as well as insertion andlocking of the set screw 316. The extension tabs can be configured tobreak away or otherwise be separated from the arms 318, 320. The innersurfaces of each of the arms 318, 320 can be configured to mate with thesecond set screw 316. For example, the inner surfaces of the arms 318,320 can include threads that correspond to external threads formed onthe second set screw 316. Accordingly, rotation of the second set screw316 with respect to the body 302 about the axis A1 can be effective totranslate the set screw with respect to the body axially along the axisA1.

The body 302 can include a cantilevered wing portion 330 that definesthe first rod-receiving recess 304. A rod R1 disposed in the firstrod-receiving recess 304 can have a central longitudinal rod axis A4.The axis A4 can be parallel to the axis A2 as shown, or can beperpendicular or obliquely angled with respect to the axis A2. The wingportion 330 can extend radially-outward from the second arm 320 of thebody 302. The wing portion 330 can have a width 330W and a height 330H.A ratio of the width 330W to the diameter of the first rod-receivingrecess 304 (or of a rod R1 disposed therein) can be less than about1.5:1, less than about 2:1, and/or less than about 3:1. A ratio of theheight 330H to the diameter of the first rod-receiving recess 304 (or ofa rod R1 disposed therein) can be less than about 0.5:1, less than about1:1, and/or less than about 2:1. In some embodiments, the height 330Hcan be less than about 5 mm, less than about 4 mm, and/or less thanabout 3 mm. The first rod-receiving recess 304 can be open in a lateraldirection such that a rod R1 can be inserted into the recess by movingthe connector 300 laterally with respect to the rod. In otherembodiments, the first rod-receiving recess 304 can be open in aproximal or distal direction, e.g., by flipping the orientation of thewing portion 330, the first set screw 314, and the rod pusher 308.

A tunnel 328 can be formed in the body 302 and can extend along a tunnelaxis A6 between a proximal-facing surface of the body 302 and the firstrod-receiving recess 304. The tunnel 328 can be formed in the wingportion 330 of the body 302. The tunnel 328 can have a shape that issubstantially a negative of the exterior shape of the rod pusher 308.The rod pusher 308 can be slidably disposed within the tunnel 328 suchthat the rod pusher can translate along the axis A6 with respect to thebody 302. A through-bore 324 can be formed in the body 302 such that thethrough-bore intersects with the tunnel 328. The through-bore 324 canextend perpendicular or substantially perpendicular to the axis A6. Thethrough-bore 324 can be sized to receive the leaf spring 312 therein, asdescribed further below. The through-bore 324 can be rectangular orsubstantially rectangular as shown, or can have other shapes. Thethrough-bore 324 can have a maximum height in the proximal-distaldirection that is less than a corresponding height of the leaf spring312 in its resting position. Accordingly, when disposed within thethrough-bore 324, the leaf spring 312 can be maintained in a deformedposition such that it exerts a constant biasing force on the rod pusher308. The through-bore 324 can be open at both ends or one or both endscan be closed.

A proximal end of the tunnel 328 can define a recess 326 sized toreceive at least a portion of the first set screw 314. The inner surfaceof the recess 326 can be configured to mate with the first set screw314. For example, the inner surface 326 can include threads thatcorrespond to external threads formed on the first set screw 314.Accordingly, rotation of the first set screw 314 with respect to thebody 302 about the axis A6 can be effective to translate the set screwwith respect to the body axially along the axis A6. The recess 326 canbe cylindrical as shown or can be conical or have other shapes.

As noted above, the rod pusher 308 can be slidably disposed within thetunnel 328 of the body 302 and can be configured to translate withrespect to the body along the axis A6. The rod pusher 308 can include abearing surface 344 configured to contact and bear against a rod R1disposed in the first rod-receiving recess 304. The bearing surface 344can include a distal-facing surface of the rod pusher 308. At least aportion of the bearing surface 344 can extend at an oblique angle withrespect to a longitudinal axis of the rod pusher 308 such that thebearing surface is ramped. The bearing surface 344 can be planar asshown, or can be concave, convex, pointed, sharpened, etc. For example,the bearing surface 344 can be concave and can define a section of acylinder, such that the bearing surface matches or approximates thecontour of a cylindrical rod R1 disposed in the first rod-receivingrecess 304. The rod pusher 308 can include a projection 338 or othermating feature for mating the rod pusher to the leaf spring 312. Theprojection 338 can include an undercut or reduced distal portion and anenlarged proximal portion.

The bias element can be configured to bias the rod pusher 308 towardsthe first rod-receiving recess 304. In the illustrated embodiment, thebias element is a rectangular leaf spring 312. The leaf spring 312 canbe formed from a resilient material such that, when deformed from aresting position, the leaf spring 312 tends to flex back towards theresting configuration. Accordingly, when deformed by movement of the rodpusher 308, the leaf spring 312 can exert a force against the interiorof the through-bore 326 to urge the rod pusher 308 towards the firstrod-receiving recess 304. While a flat rectangular leaf spring 312 isshown, various other bias elements can be used instead or in addition,such as spring wires, spring clips, wave springs, coil springs, and thelike. In some embodiments, the bias element can be omitted. For example,the rod pusher 308 can be free to float within the tunnel 328, or can beretained by a pin or other retention feature without being biasedtowards the first rod-receiving recess 304. The leaf spring 312 caninclude an opening 336 or other mating feature for mating the leafspring to the rod pusher 308. In the illustrated embodiment, the leafspring 312 includes a keyed opening 336 configured to mate with theprojection 338 of the rod pusher 308. The opening 336 can have a firstportion 336A with a diameter that is large enough for the enlargedproximal portion of the projection 338 to pass through the opening. Theopening 336 can have a second portion 336B with a diameter that is largeenough for the reduced distal portion of the projection 338 to passthrough the opening but not large enough for the enlarged proximalportion of the projection 338 to pass through the opening. The leafspring 312 can thus be configured to retain the rod pusher 308 withinthe body 302 and vice versa.

Assembly of the leaf spring 312 to the rod pusher 308 is illustratedschematically in FIGS. 3C-3E. As shown in FIG. 3C, the rod pusher 308can be inserted into the tunnel 328 and positioned distal to thethrough-bore 324. The leaf spring 312 can be inserted into thethrough-bore 324 to position the first portion 336A of the opening 336in line with the projection 338 of the rod pusher 308, as shown in FIG.3D. The rod pusher 308 can be moved proximally to pass the projection338 through the first portion 336A of the opening 336, and then the leafspring 312 can be inserted further into the through-bore 324 to positionthe projection 338 in the second portion 336B of the opening 336, asshown in FIG. 3E. In this position, the enlarged proximal portion of theprojection 338 sits proximal to the leaf spring 312 and cannot passthrough the opening 336, thereby retaining the rod pusher 308 within thebody 302. The spring force of the leaf spring 312 acting against theinterior of the through-bore 324 can be effective to retain the leafspring within the through-bore.

The first set screw 314 can include an exterior thread configured tomate with the interior threads of the recess 326 to allow the first setscrew to be advanced or retracted along the axis A6 with respect to thebody 302 by rotating the first set screw about the axis A6. The firstset screw 314 can include a driving interface 346 configured to receivea driver for applying a rotational force to the first set screw aboutthe axis A6. The distal surface of the first set screw 314 can beconfigured to contact and bear against a portion of the rod pusher 308,e.g., the projection 338, to urge the rod pusher 308 against a rod R1disposed in the first rod-receiving 304 recess and lock the rod to theconnector 300. When tightened against the rod pusher 308 and, byextension, the rod R1, the first set screw 314 can prevent the rod fromtranslating relative to the connector 300 along the axis A4 and/or fromrotating with respect to the connector about the axis A4. While a firstset screw 314 is shown, it will be appreciated that other lockingelements can be used instead or addition, such as a closure cap thatadvances and locks by quarter-turn rotation, a closure cap that slidesin laterally without rotating, a nut that threads onto an exterior ofthe connector 300, and so forth.

The second set screw 316 can include an exterior thread configured tomate with the interior threads formed on the arms 318, 320 of the body302 to allow the second set screw to be advanced or retracted along theaxis A1 with respect to the body by rotating the second set screw aboutthe axis A1. The second set screw 316 can include a driving interface348 configured to receive a driver for applying a rotational force tothe second set screw about the axis A1. The distal surface of the secondset screw 316 can be configured to contact and bear against a rod R2disposed in the second rod-receiving 306 recess to lock the rod to theconnector 300. When tightened against the rod R2, the second set screw316 can prevent the rod from translating relative to the connector 300along the axis A2 and/or from rotating with respect to the connectorabout the axis A2. While a second set screw 316 is shown, it will beappreciated that other locking elements can be used instead or addition,such as a closure cap that advances and locks by quarter-turn rotation,a closure cap that slides in laterally without rotating, a nut thatthreads onto an exterior of the connector 300, and so forth.

Operation of the connector 300 is illustrated schematically in FIGS.3F-3H.

As shown in FIG. 3F, the connector 300 can have a resting configurationin which no rod is disposed in the first or second rod-receivingrecesses 304, 306. In this configuration, the biasing force of the leafspring 312 can cause the rod pusher 308 to slide distally towards thefirst rod-receiving recess 304.

In the resting configuration, the wing portion 330 of the body 302 andthe distal end of the rod pusher 308 can define an aperture 350 that issmaller than the diameter of a first rod R1 to which the connector 300is to be coupled. Accordingly, as shown in FIG. 3G, as the rod R1 isinserted into the first rod-receiving recess 304, the rod bears againstthe rod pusher 308 to move the connector 300 out of the restingconfiguration. Insertion of the rod R1 can move the rod pusher 308proximally along the axis A6, thereby compressing the leaf spring 312within the through-bore 324. As the largest cross-sectional portion ofthe rod R1 is positioned in the aperture 350, the rod pusher 308 can bedisplaced to its furthest distance from the first rod-receiving recess304.

As shown in FIG. 3H, once the largest cross-sectional portion of the rodR1 clears the aperture 350 as the rod is seated in the firstrod-receiving recess 304, the biasing force of the leaf spring 312 cancause the rod pusher 308 to move distally, back along the axis A6towards the first rod-receiving recess. This movement can at leastpartially close the aperture 350 around the rod R1 to capture the rod inthe first rod-receiving recess 304. The biasing force of the leaf spring312 can resist retrograde movement of the rod pusher 308 and thus resistdisconnection of the connector 300 from the first rod R1. The leafspring 312 can be at least partially compressed when the rod R1 is fullyseated in the recess 304, such that the rod pusher 308 exerts acontinuous drag force on the rod R1. When the connector 300 ispositioned as desired with respect to the first rod R1, the first setscrew 314 can be tightened to lock the rod in the first rod-receivingrecess 304. As the first set screw 314 is tightened, the rod pusher 308can be pressed distally, firmly into contact with the rod R1. When thefirst set screw 314 is tightened, the connector 300 can be locked to thefirst rod R1 to resist or prevent translation of the rod R1 with respectto the connector along the axis A4 and to resist or prevent rotation ofthe rod R1 with respect to the connector about the axis A4. A second rodR2 can be positioned in the second rod-receiving recess 306 and thesecond set screw 316 can be tightened to lock the rod R2 to the body302.

The connector 300 can thus be used to connect a first spinal rod R1 to asecond spinal rod R2. While use of the connector 300 with first andsecond spinal rods is generally described herein, it will be appreciatedthat the connector can instead be configured for use with other types oforthopedic hardware, whether implanted or external. For example, one orboth halves of the connector 300 can be modified to couple other variouscomponents to each other (e.g., to couple a rod to a plate, to couple aplate to a plate, to couple a rod to cable, to couple a cable to acable, and so forth). By way of further example, half of the connector300, e.g., the portion of the body in which the second rod-receivingrecess 306 is formed, can be replaced with an integral rod, a transversebar, a cable connector, a plate with an opening formed therein forreceiving a bone anchor, and so forth. In some embodiments, thestructure of the connector 300 for attaching the second rod R2 can be amirror image of the opposite half of the connector 300. In other words,the connector 300 can include two leaf springs 312, two rod pushers 308,etc.

The connector 300 can provide various benefits for the user and/orpatient. For example, the biased rod pusher 308 can provide tactilefeedback when the connector 300 is “snapped” onto the first rod R1,giving the user confidence that the rod has been attached successfullybefore tightening the connector. The biased rod pusher 308 can alsoapply friction or “drag” to the rod R1 prior to locking the set screw314, helping to keep the connector 300 in place and prevent “flopping”while still allowing free movement when intended by the user. The snapand drag features of the connector 300 can be completely independent ofthe set screw 314, such that the connector can snap and drag onto a rodR1 regardless of whether the set screw 314 is tightened or even presentin the connector. By way of further example, the low-profile geometry ofthe wing portion 330 of the connector 300 can allow the connector to beused in surgical areas where space is limited (e.g., in the cervicalarea of the spine). In an exemplary method, the wing portion 330 of theconnector 300 can be hooked onto a first rod R1 at a location betweentwo bone anchors to which the rod is coupled, the two bone anchors beingimplanted in adjacent vertebral levels of the cervical spine. As yetanother example, the connector 300 can facilitate independent locking ofthe first and second rods R1, R2. This can allow the connector 300 to belocked to the first rod R1 to limit or prevent movement of the connectorbefore the second rod R2 is attached and/or locked.

FIGS. 4A-4K illustrate an exemplary embodiment of a connector 400.Except as indicated below and as will be readily appreciated by onehaving ordinary skill in the art, the structure and operation of theconnector 400 is substantially similar to that of the connector 300, andtherefore a detailed description is omitted here for the sake ofbrevity.

As shown, the connector 400 can include a body 402 that defines firstand second rod-receiving recesses 404, 406, a rod pusher 408, a biaselement or spring wire 412, a first locking element or set screw 414,and a second locking element or set screw 416. The rod pusher 408 can bebiased by the spring wire 412 in a direction that urges the rod pusherinto a first rod R1 disposed in the first rod-receiving recess 404. Thefirst set screw 414 can be tightened to lock the connector 400 to thefirst rod R1. The second set screw 416 can be tightened to lock a secondrod R2 in the second rod-receiving recess 406 of the connector 400. Theillustrated connector 400 can thus allow for independent locking offirst and second rods R1, R2 to the connector. The connector 400 caninclude one or more low-profile portions to facilitate use in tightspaces. For example, the first rod-receiving recess 404 can be formed ina portion 430 of the connector body 402 having a reduced-profile, e.g.,to fit between bone anchors implanted in adjacent levels of the cervicalspine.

The body 402 can include proximal and distal ends 402 p, 402 d thatdefine a proximal-distal axis A1. The proximal end 402 p of the body 402can include a pair of spaced apart arms 418, 420 that define the secondrod-receiving recess 406 therebetween. A rod R2 disposed in the secondrod-receiving recess 406 can have a central longitudinal rod axis A2.

As shown for example in FIG. 4C, a spring wire 412 can be used to biasthe rod pusher 408 towards the first rod-receiving recess 404, insteadof or in addition to the leaf spring 312 of the connector 300. The rodpusher 408 can include a through bore 426 sized to receive the springwire 412 therein. In at least some positions of the rod pusher 408 withrespect to the body 402, the through-bore 426 of the rod pusher can bealigned with the through-bore 424 of the body, such that the spring wire412 extends through both through-bores 424, 426. The through-bore 426can include a middle portion and opposed end portions. The middleportion of the through-bore 426 can approximate the dimensions of thespring wire 412. For example, the middle portion can be cylindrical andcan have a diameter that is substantially equal to the diameter of thespring wire 412. The end portions of the through-bore 426 can beelongated or can otherwise have a dimension greater than the diameter ofthe spring wire 412 to allow the rod pusher 408 to translate along thetunnel axis A6 and to accommodate the bend radius of the spring wire 412during such translation. The longitudinal axes of the through-bores 424,426 and the spring wire 412 can extend perpendicular or substantiallyperpendicular to the axis A6 and parallel or substantially parallel tothe axis A4, as shown in FIG. 4C. Alternatively, as shown in FIG. 4D,the longitudinal axes of the through-bores 424, 426 and the spring wire412 can extend perpendicular or substantially perpendicular to the axisA6 and perpendicular or substantially perpendicular to the axis A4.

As shown in FIGS. 4H-4J, the rod pusher 408 can be configured totranslate along the axis A6 within a tunnel 428 formed in the body 402.The rod pusher 408 can translate within the tunnel 428 under the bias ofthe spring wire 412 to provide a snap and drag feature with respect tothe first rod R1.

In other embodiments, the rod pusher 408 can pivot with respect to thebody 402 about a rotation axis instead of or in addition to translating.For example, as shown in FIG. 4K, the rod pusher 408 can be pivotallymounted within the tunnel 428 on a pivot pin or axle 452. The rod pusher408 can therefore rotate along the arc A7 as a rod R1 is inserted intothe first rod-receiving recess 404. Apart from this pivoting movement,operation of the connector 400 shown in FIG. 4K is the same as describedabove.

FIGS. 5A-5F illustrate an exemplary embodiment of a connector 500. Asshown, the connector 500 can include a body 502 that defines first andsecond rod-receiving recesses 504, 506, a rod pusher 508, a bias elementor leaf spring 512, and a locking element or set screw 516. The rodpusher 508 can be configured to translate laterally within the body 502,and can be biased by the leaf spring 512 in a direction that urges therod pusher into a first rod R1 disposed in the first rod-receivingrecess 504. The set screw 516 can be tightened to lock the connector 500to both the first rod R1 and to a second rod R2 disposed in the secondrod-receiving recess 506. The illustrated connector 500 can thus allowfor one-step locking of first and second rods R1, R2 to the connector.The connector 500 can include one or more low-profile portions tofacilitate use in tight spaces. For example, the first rod-receivingrecess 504 can be formed in a portion of the connector body 502 having areduced-profile, e.g., to fit between bone anchors implanted in adjacentlevels of the cervical spine.

The body 502 can include proximal and distal ends 502 p, 502 d thatdefine a proximal-distal axis A1. The proximal end 502 p of the body 502can include a pair of spaced apart arms 518, 520 that define the secondrod-receiving recess 506 therebetween. A rod R2 disposed in the secondrod-receiving recess 506 can have a central longitudinal rod axis A2.The second rod-receiving recess 506 can be open in a proximal direction,such that a rod R2 can be inserted into the recess by moving the roddistally with respect to the connector 500. Each of the arms 518, 520can extend from the distal portion 502 d of the body 502 to a free end.The outer surfaces of each of the arms 518, 520 can include a feature(not shown), such as a recess, dimple, notch, projection, or the like,to facilitate coupling of the connector 500 to various instruments. Forexample, the outer surface of each arm 518, 520 can include an arcuategroove at the respective free end of the arms for attaching theconnector 500 to an extension tower or retractor. The arms 518, 520 caninclude or can be coupled to extension or reduction tabs (not shown)that extend proximally from the body 502 to functionally extend thelength of the arms 518, 520. The extension tabs can facilitate insertionand reduction of a rod or other implant, as well as insertion andlocking of the set screw 516. The extension tabs can be configured tobreak away or otherwise be separated from the arms 518, 520. The innersurfaces of each of the arms 518, 520 can be configured to mate with theset screw 516. For example, the inner surfaces of the arms 518, 520 caninclude threads that correspond to external threads formed on the setscrew 516. Accordingly, rotation of the set screw 516 with respect tothe body 502 about the axis A1 can be effective to translate the setscrew with respect to the body axially along the axis A1.

The distal end 502 d of the body 502 can define a tunnel 528 in whichthe rod pusher 508 can be disposed. The tunnel 528 can extend along arod pusher axis A3 between the second rod-receiving recess 506 and thefirst rod-receiving recess 504. The rod pusher 508 can be configured totranslate within the tunnel 528 along the axis A3. The axis A3 can beperpendicular or substantially perpendicular to the axis A1. The axis A3can also be perpendicular or substantially perpendicular to the axis A2.The axis A3 can extend from the axis A1 at an angle in the range ofabout 60 degrees to about 120 degrees. The tunnel 528 can have a shapethat is substantially a negative of the exterior shape of the rod pusher508. The tunnel 528 can include opposed recesses 524 formed thereinsized to receive respective ends of the leaf spring 512. As shown inFIGS. 5C-5E, the recesses 524 can be formed by drilling bore holes 558into the distal-facing surface of the body 502, such that the bore holes558 intersect with the tunnel 528. Alternatively, the recesses 524 canbe formed by a lateral through-bore similar to the through-bore 224 ofthe connector 200 described above, but instead beingvertically-elongated or otherwise dimensioned to receive the leaf spring512.

The body 502 can include a cantilevered wing portion 530 that definesthe first rod-receiving recess 504. A rod R1 disposed in the firstrod-receiving recess 504 can have a central longitudinal rod axis A4.The axis A4 can be parallel to the axis A2 as shown, or can beperpendicular or obliquely angled with respect to the axis A2. The wingportion 530 can extend radially-outward from the second arm 520 of thebody 502. The wing portion 530 can have a width 530W and a height 530H.A ratio of the width 530W to the diameter of the first rod-receivingrecess 504 (or of a rod R1 disposed therein) can be less than about1.5:1, less than about 5:1, and/or less than about 3:1. A ratio of theheight 530H to the diameter of the first rod-receiving recess 504 (or ofa rod R1 disposed therein) can be less than about 0.5:1, less than about1:1, and/or less than about 5:1. In some embodiments, the height 530Hcan be less than about 5 mm, less than about 4 mm, and/or less thanabout 3 mm. The first rod-receiving recess 504 can be open in a distaldirection such that a rod R1 can be inserted into the recess by movingthe connector 500 distally with respect to the rod. In otherembodiments, the first rod-receiving recess 504 can be open in aproximal direction, e.g., by flipping the wing portion 530 and formingit such that it extends from a distal portion of the body 502, or in alateral direction.

As noted above, the rod pusher 508 can be slidably disposed within thetunnel 528 of the body 502 and can be configured to translate withrespect to the body along the axis A3. The rod pusher 508 can include afirst bearing surface 544A configured to contact and bear against afirst rod R1 disposed in the first rod-receiving recess 504. The bearingsurface 544A can extend at an oblique angle with respect to alongitudinal axis of the rod pusher 508 such that the bearing surface isramped. The bearing surface 544A can be planar as shown, or can beconvex, concave, pointed, sharpened, etc. For example, the bearingsurface 544A can be concave and can define a section of a cylinder, suchthat the bearing surface matches or approximates the contour of acylindrical rod R1 disposed in the first rod-receiving recess 504. Therod pusher 508 can include a second bearing surface 544B configured tocontact and bear against a second rod R2 disposed in the secondrod-receiving recess 506. The bearing surface 544B can extend at anoblique angle with respect to a longitudinal axis of the rod pusher 508such that the bearing surface is ramped. The bearing surface 544B can beplanar as shown, or can be convex, concave, pointed, sharpened, etc. Forexample, the bearing surface 544B can be concave and can define asection of a cylinder, such that the bearing surface matches orapproximates the contour of a cylindrical rod R2 disposed in the secondrod-receiving recess 506.

The rod pusher 508 can include a through-bore 526. The through-bore 526can extend perpendicular or substantially perpendicular to the axis A3.The through-bore 526 can be sized to receive the leaf spring 512therein. In at least some positions of the rod pusher 508 with respectto the body 502, the through-bore 526 of the rod pusher can be alignedwith the recesses 524 of the body, such that the leaf spring 512 extendsthrough the through-bore 526 and into the opposed recesses 524. As shownin FIG. 5F, the through-bore 526 can include a middle portion andopposed end portions. The middle portion of the through-bore 526 canapproximate the dimensions of the leaf spring 512. For example, themiddle portion can have a width that is substantially equal to thethickness of the leaf spring 512. The end portions of the through-bore526 can be elongated or can otherwise have a dimension greater than thethickness of the leaf spring 512 to allow the rod pusher 508 totranslate along the axis A3 and to accommodate the bend radius of theleaf spring 512 during such translation.

As shown, the internal geometry of the through-bore 526 can be definedat least in part by a pin 560. In particular, the pin 560 can define thereduced-width middle portion of the through-bore 526. The pin 560 can beinserted through a pin hole 562 formed in the rod pusher 508 thatintersects with the through-bore 526. The pin hole 562 can extendperpendicular or substantially perpendicular to the axis A3 and parallelor substantially parallel to the axis A1. Forming the internal geometryof the through-bore 526 in this manner can advantageously reduce thecomplexity of the manufacturing process as compared, for example, withforming the internal geometry as shown in FIG. 2D above.

The connector 500 can be assembled by inserting the leaf spring 512through the through-bore 526 formed in the rod pusher 508 and theninserting the rod pusher 508 into the tunnel 528 of the body 502. As therod pusher 508 is inserted into the body 502, the ends of the leafspring 512 can be temporarily deformed against sidewalls of the tunneluntil the ends are aligned with and snap into the recesses 524 formed inthe tunnel.

The bias element can be configured to bias the rod pusher 508 towardsthe first rod-receiving recess 504. In the illustrated embodiment, thebias element is a rectangular leaf spring 512. The leaf spring 512 canbe formed from a resilient material such that, when deformed from astraight line, the leaf spring tends to flex back towards its straightresting configuration. Accordingly, when deformed by movement of the rodpusher 508, the leaf spring 512 can exert a force against the interiorof the through-bore 526 to urge the rod pusher 508 towards the firstrod-receiving recess 504. While a straight, rectangular leaf spring 512is shown, various other bias elements can be used instead or inaddition, such as non-straight or non-rectangular leaf springs, springwires, spring clips, wave springs, coil springs, and the like. In someembodiments, the bias element can be omitted. For example, the rodpusher 508 can be free to float within the tunnel 528, or can beretained by a pin or other retention feature without being biasedtowards the first rod-receiving recess 504. Use of a relatively flatleaf spring 512 as shown can, in some embodiments, provide certainadvantages. For example, a cylindrical spring wire may need to be madevery thin to provide the desired spring force, which can makemanufacturing and assembly of the connector 500 challenging. By using arelatively flat leaf spring 512, the bias element can be made thinenough to provide the desired spring force without making manufacturingor assembly more difficult. Also, a relatively flat leaf spring 512 canbe less prone to rotation, making it easier to constrain movement of thebias element and/or limiting rotation of the rod pusher 508 within thetunnel 528.

The set screw 516 can include an exterior thread configured to mate withthe interior threads formed on the arms 518, 520 of the body 502 toallow the set screw to be advanced or retracted along the axis A1 withrespect to the body by rotating the set screw about the axis A1. The setscrew 516 can include a driving interface 548 configured to receive adriver for applying a rotational force to the set screw about the axisA1. The distal surface of the set screw 516 can be configured to contactand bear against a rod R2 disposed in the second rod-receiving 506recess to lock the rod to the connector 500. When tightened against therod R2, the set screw 516 can prevent the rod from translating relativeto the connector 500 along the axis A2 and/or from rotating with respectto the connector about the axis A2. While a set screw 516 is shown, itwill be appreciated that other locking elements can be used instead oraddition, such as a closure cap that advances and locks by quarter-turnrotation, a closure cap that slides in laterally without rotating, a nutthat threads onto an exterior of the connector 500, and so forth.

As will be appreciated by one having ordinary skill in the art havingreviewed the present disclosure, operation of the connector 500 issubstantially the same as that of the connector 200 described above.Accordingly, a detailed description is omitted here for the sake ofbrevity. Any of the features described above with respect to theconnector 200, including those shown in FIGS. 2I-2L, can be applied tothe connector 500.

The connector 500 can thus be used to connect a first spinal rod R1 to asecond spinal rod R2. While use of the connector 500 with first andsecond spinal rods is generally described herein, it will be appreciatedthat the connector can instead be configured for use with other types oforthopedic hardware, whether implanted or external. For example, one orboth halves of the connector 500 can be modified to couple other variouscomponents to each other (e.g., to couple a rod to a plate, to couple aplate to a plate, to couple a rod to cable, to couple a cable to acable, and so forth).

The connector 500 can provide various benefits for the user and/orpatient. For example, the biased rod pusher 508 can provide tactilefeedback when the connector 500 is “snapped” onto the first rod R1,giving the user confidence that the rod has been attached successfullybefore tightening the connector. The biased rod pusher 508 can alsoapply friction or “drag” to the rod R1 prior to locking the set screw516, helping to keep the connector in place and prevent “flopping” whilestill allowing free movement when intended by the user. By way offurther example, the low-profile geometry of the wing portion 530 of theconnector 500 can allow the connector to be used in surgical areas wherespace is limited (e.g., in the cervical area of the spine). In anexemplary method, the wing portion 530 of the connector 500 can behooked onto a first rod R1 at a location between two bone anchors towhich the rod is coupled, the two bone anchors being implanted inadjacent vertebral levels of the cervical spine. As yet another example,the connector 500 can facilitate simultaneous and/or single-step lockingof the first and second rods R1, R2. This can allow the connector 500 tobe locked to both rods R1, R2 with minimal steps. In other embodiments,the connector 500 can facilitate independent locking of the rods R1, R2,e.g., with use of a saddle and dual set screw.

FIGS. 6A-6F illustrate an exemplary embodiment of a connector 600. Asshown, the connector 600 can include a body 602 that defines first andsecond rod-receiving recesses 604, 606, a rod pusher 608, a bias elementor leaf spring 612, a first locking element or set screw 614, and asecond locking element or set screw 616. The rod pusher 608 can beconfigured to translate laterally within the body 602, and can be biasedby the leaf spring 612 in a direction that urges the rod pusher into afirst rod R1 disposed in the first rod-receiving recess 604. The firstset screw 614 can be tightened to lock the connector 600 to the firstrod R1. The second set screw 616 can be tightened to lock a second rodR2 in the second rod-receiving recess 606 of the connector 600. Theillustrated connector 600 can thus allow for independent locking offirst and second rods R1, R2 to the connector. The connector 600 caninclude one or more low-profile portions to facilitate use in tightspaces. For example, the first rod-receiving recess 604 can be formed ina portion of the connector body 602 having a reduced-profile, e.g., tofit between bone anchors implanted in adjacent levels of the cervicalspine.

The body 602 can include proximal and distal ends 602 p, 602 d thatdefine a proximal-distal axis A1. The proximal end 602 p of the body 602can include a pair of spaced apart arms 618, 620 that define the secondrod-receiving recess 606 therebetween. A rod R2 disposed in the secondrod-receiving recess 606 can have a central longitudinal rod axis A2.The second rod-receiving recess 606 can be open in a proximal direction,such that a rod R2 can be inserted into the recess by moving the roddistally with respect to the connector 600. Each of the arms 618, 620can extend from the distal portion 602 d of the body 602 to a free end.The outer surfaces of each of the arms 618, 620 can include a feature(not shown), such as a recess, dimple, notch, projection, or the like,to facilitate coupling of the connector 600 to various instruments. Forexample, the outer surface of each arm 618, 620 can include an arcuategroove at the respective free end of the arms for attaching theconnector 600 to an extension tower or retractor. The arms 618, 620 caninclude or can be coupled to extension or reduction tabs (not shown)that extend proximally from the body 602 to functionally extend thelength of the arms 618, 620. The extension tabs can facilitate insertionand reduction of a rod or other implant, as well as insertion andlocking of the second set screw 616. The extension tabs can beconfigured to break away or otherwise be separated from the arms 618,620. The inner surfaces of each of the arms 618, 620 can be configuredto mate with the second set screw 616. For example, the inner surfacesof the arms 618, 620 can include threads that correspond to externalthreads formed on the second set screw 616. Accordingly, rotation of thesecond set screw 616 with respect to the body 602 about the axis A1 canbe effective to translate the set screw with respect to the body axiallyalong the axis A1.

The distal end 602 d of the body 602 can define a tunnel 628 in whichthe rod pusher 608 can be disposed. The tunnel 628 can extend along arod pusher axis A3 between the second rod-receiving recess 606 and thefirst rod-receiving recess 604. The rod pusher 608 can be configured totranslate within the tunnel 628 along the axis A3. The axis A3 can beperpendicular or substantially perpendicular to the axis A1. The axis A3can also be perpendicular or substantially perpendicular to the axis A2.The axis A3 can extend from the axis A1 at an angle in the range ofabout 60 degrees to about 120 degrees. The tunnel 628 can have a shapethat is substantially a negative of the exterior shape of the rod pusher608. The tunnel 628 can include opposed recesses 624 formed thereinsized to receive respective ends of the leaf spring 612. The recesses624 can be formed by drilling bore holes into the distal-facing surfaceof the body 602, such that the bore holes intersect with the tunnel 628,as described above with respect to FIGS. 5C-5E. Alternatively, therecesses 624 can be formed by a lateral through-bore similar to thethrough-bore 224 of the connector 200 described above, but instead beingvertically-elongated or otherwise dimensioned to receive the leaf spring612.

The distal end 602 d of the body 602 can define a recess 664 sized toreceive at least a portion of the first set screw 614, as shown forexample in FIG. 6E. The recess 664 can be formed distal to the tunnel628. The inner surface of the recess 664 can be configured to mate withthe first set screw 614. For example, the inner surface can includethreads that correspond to external threads formed on the first setscrew 614. Accordingly, rotation of the first set screw 614 with respectto the body 602 about the axis A1 can be effective to translate the setscrew with respect to the body axially along the axis A1.

The body 602 can include a cantilevered wing portion 630 that definesthe first rod-receiving recess 604. A rod R1 disposed in the firstrod-receiving recess 604 can have a central longitudinal rod axis A4.The axis A4 can be parallel to the axis A2 as shown, or can beperpendicular or obliquely angled with respect to the axis A2. The wingportion 630 can extend radially-outward from the second arm 620 of thebody 602. The wing portion 630 can have a width 630W and a height 630H.A ratio of the width 630W to the diameter of the first rod-receivingrecess 604 (or of a rod R1 disposed therein) can be less than about1.5:1, less than about 6:1, and/or less than about 3:1. A ratio of theheight 630H to the diameter of the first rod-receiving recess 604 (or ofa rod R1 disposed therein) can be less than about 0.5:1, less than about1:1, and/or less than about 6:1. In some embodiments, the height 630Hcan be less than about 5 mm, less than about 4 mm, and/or less thanabout 3 mm. The first rod-receiving recess 604 can be open in a distaldirection such that a rod R1 can be inserted into the recess by movingthe connector 600 distally with respect to the rod. In otherembodiments, the first rod-receiving recess 604 can be open in aproximal direction, e.g., by flipping the wing portion 630 and formingit such that it extends from a distal portion of the body 602, or in alateral direction.

As noted above, the rod pusher 608 can be slidably disposed within thetunnel 628 of the body 602 and can be configured to translate withrespect to the body along the axis A3. The rod pusher 608 can include afirst bearing surface 644A configured to contact and bear against afirst rod R1 disposed in the first rod-receiving recess 604. The bearingsurface 644A can extend at an oblique angle with respect to alongitudinal axis of the rod pusher 608 such that the bearing surface isramped. The bearing surface 644A can be planar as shown, or can beconvex, concave, pointed, sharpened, etc. For example, the bearingsurface 644A can be concave and can define a section of a cylinder, suchthat the bearing surface matches or approximates the contour of acylindrical rod R1 disposed in the first rod-receiving recess 604.

The rod pusher 608 can include a second bearing surface 644B configuredto contact and bear against a corresponding bearing surface of the firstset screw 614, as described further below. The bearing surface 644B canextend at an oblique angle with respect to a longitudinal axis of therod pusher 608 such that the bearing surface is ramped. The bearingsurface 644B can be conical as shown, or can be planar, convex, concave,pointed, sharpened, etc.

The rod pusher 608 can include a third bearing surface 644C configuredto contact and bear against a second rod R2 disposed in the secondrod-receiving recess 606. The bearing surface 644C can extend at anoblique angle with respect to a longitudinal axis of the rod pusher 608such that the bearing surface is ramped. The bearing surface 644C can beplanar as shown, or can be convex, concave, pointed, sharpened, etc. Forexample, the bearing surface 644C can be concave and can define asection of a cylinder, such that the bearing surface matches orapproximates the contour of a cylindrical rod R2 disposed in the secondrod-receiving recess 606. It will be appreciated that the third bearingsurface 644C can be omitted and/or need not necessarily contact thesecond rod R2.

The rod pusher 608 can include a through-bore 626. The through-bore 626can extend perpendicular or substantially perpendicular to the axis A3.The through-bore 626 can be sized to receive the leaf spring 612therein. In at least some positions of the rod pusher 608 with respectto the body 602, the through-bore 626 of the rod pusher can be alignedwith the recesses 624 of the body, such that the leaf spring 612 extendsthrough the through-bore 626 and into the opposed recesses 624. Thethrough-bore 626 can include a middle portion and opposed end portions,e.g., in a manner similar to the through-bore 526 described above withrespect to FIG. 5F. The middle portion of the through-bore 626 canapproximate the dimensions of the leaf spring 612. For example, themiddle portion can have a width that is substantially equal to thethickness of the leaf spring 612. The end portions of the through-bore626 can be elongated or can otherwise have a dimension greater than thethickness of the leaf spring 612 to allow the rod pusher 608 totranslate along the axis A3 and to accommodate the bend radius of theleaf spring 612 during such translation.

As shown, the internal geometry of the through-bore 626 can be definedat least in part by a pin 660. In particular, the pin 660 can define thereduced-width middle portion of the through-bore 626. The pin 660 can beinserted through a pin hole 662 formed in the rod pusher 608 thatintersects with the through-bore 626. The pin hole 662 can extendperpendicular or substantially perpendicular to the axis A3 and parallelor substantially parallel to the axis A1. Forming the internal geometryof the through-bore 626 in this manner can advantageously reduce thecomplexity of the manufacturing process as compared, for example, withforming the internal geometry as shown in FIG. 2D above.

The connector 600 can be assembled by inserting the leaf spring 612through the through-bore 626 formed in the rod pusher 608 and theninserting the rod pusher 608 into the tunnel 628 of the body 602. As therod pusher 608 is inserted into the body 602, the ends of the leafspring 612 can be temporarily deformed against sidewalls of the tunneluntil the ends are aligned with and snap into the recesses 624 formed inthe tunnel.

The bias element can be configured to bias the rod pusher 608 towardsthe first rod-receiving recess 604. In the illustrated embodiment, thebias element is a rectangular leaf spring 612. The leaf spring 612 canbe formed from a resilient material such that, when deformed from astraight line, the leaf spring tends to flex back towards its straightresting configuration. Accordingly, when deformed by movement of the rodpusher 608, the leaf spring 612 can exert a force against the interiorof the through-bore 626 to urge the rod pusher 608 towards the firstrod-receiving recess 604. While a straight, rectangular leaf spring 612is shown, various other bias elements can be used instead or inaddition, such as non-straight or non-rectangular leaf springs, springwires, spring clips, wave springs, coil springs, and the like. In someembodiments, the bias element can be omitted. For example, the rodpusher 608 can be free to float within the tunnel 628, or can beretained by a pin or other retention feature without being biasedtowards the first rod-receiving recess 604. Use of a relatively flatleaf spring 612 as shown can, in some embodiments, provide certainadvantages. For example, a cylindrical spring wire may need to be madevery thin to provide the desired spring force, which can makemanufacturing and assembly of the connector 600 challenging. By using arelatively flat leaf spring 612, the bias element can be made thinenough to provide the desired spring force without making manufacturingor assembly more difficult. Also, a relatively flat leaf spring 612 canbe less prone to rotation, making it easier to constrain movement of thebias element and/or limiting rotation of the rod pusher 608 within thetunnel 628.

In some embodiments, for example as shown in FIG. 6F, the bias elementcan be a spring wire 612 similar to the spring wire 212 of the connector200 described above.

In some embodiments, the internal geometry of the through-bore 626formed in the rod pusher 608 can be formed in a manner similar to thatof the rod pusher 208 in the connector 200 described above.

The first set screw 614 can include a proximal portion 614 p and adistal portion 614 d. The proximal portion 614 p of the first set screw614 can define a bearing surface configured to contact and bear againstthe second bearing surface 644B of the rod pusher 608. In theillustrated embodiment, the proximal portion 614 p of the first setscrew 614 defines a frustoconical ramped bearing surface thatcorresponds to the ramped bearing surface 644B of the rod pusher 608.The proximal portion 614 p of the first set screw 614 can include adriving interface 646 configured to receive a driver for applying arotational force to the first set screw about the axis A1. The distalportion 614 d of the first set screw 614 can include an exterior threadconfigured to mate with the interior threads of the recess 664 to allowthe first set screw to be advanced or retracted along the axis A1 withrespect to the body 602 by rotating the first set screw about the axisA1. While a first set screw 614 is shown, it will be appreciated thatother locking elements can be used instead or addition, such as aclosure cap that advances and locks by quarter-turn rotation, a closurecap that slides in laterally without rotating, and so forth. In someembodiments, the first set screw is short enough in the verticaldimension so that it does not interfere with a rod R2 seated in thesecond rod recess 606. In other embodiments, the rod R2 can bear againstthe proximal end of the first set screw 614 when locked to the connector600.

The second set screw 616 can include an exterior thread configured tomate with the interior threads formed on the arms 618, 620 of the body602 to allow the second set screw to be advanced or retracted along theaxis A1 with respect to the body by rotating the second set screw aboutthe axis A1. The second set screw 616 can include a driving interface648 configured to receive a driver for applying a rotational force tothe set screw about the axis A1. The distal surface of the second setscrew 616 can be configured to contact and bear against a rod R2disposed in the second rod-receiving 606 recess to lock the rod to theconnector 600. When tightened against the rod R2, the second set screw616 can prevent the rod from translating relative to the connector 600along the axis A2 and/or from rotating with respect to the connectorabout the axis A2. While a second set screw 616 is shown, it will beappreciated that other locking elements can be used instead or addition,such as a closure cap that advances and locks by quarter-turn rotation,a closure cap that slides in laterally without rotating, a nut thatthreads onto an exterior of the connector 600, and so forth.

In operation, the connector 600 can have a resting configuration inwhich no rod is disposed in the first or second rod-receiving recesses604, 606. In this configuration, the biasing force of the leaf spring612 can cause the rod pusher 608 to slide towards the firstrod-receiving recess 604.

In the resting configuration, the wing portion 630 of the body 602 andthe free end of the rod pusher 608 can define an aperture 650 that issmaller than the diameter of a first rod R1 to which the connector 600is to be coupled. Accordingly, as the rod R1 is inserted into the firstrod-receiving recess 604, the rod bears against the rod pusher 608 tomove the connector 600 out of the resting configuration. Insertion ofthe rod R1 can move the rod pusher 608 along the axis A3, therebydeforming the leaf spring 612 from its resting state. As the largestcross-sectional portion of the rod R1 is positioned in the aperture 650,the rod pusher 608 can be displaced to its furthest distance from thefirst rod-receiving recess 604.

Once the largest cross-sectional portion of the rod R1 clears theaperture 650 as the rod is seated in the first rod-receiving recess 604,the biasing force of the leaf spring 612 can cause the rod pusher 608 tomove back along the axis A3 towards the first rod-receiving recess. Thismovement can at least partially close the aperture 650 around the rod R1to capture the rod in the first rod-receiving recess 604. The biasingforce of the leaf spring 612 can resist retrograde movement of the rodpusher 608 and thus resist disconnection of the connector 600 from thefirst rod R1.

The geometry of the connector 600 can be selected such that, when therod R1 is fully seated in the first rod-receiving recess 604, the leafspring 612 is deformed from its resting state. The leaf spring 612 canthus press the rod pusher 608 against the rod R1 to provide a frictionor drag effect, before the set screws 614, 616 are tightened and/orbefore a second rod R2 is positioned in the connector 600.

When the connector 600 is positioned as desired with respect to thefirst rod R1, the first set screw 614 can be advanced proximallyrelative to the body 602 to lock the rod in the first rod-receivingrecess 604. As the first set screw 614 is advanced proximally, e.g., byrotating the first set screw 614 about the axis A1, the ramped surfaceof the first set screw can bear against the ramped surface 644B of therod pusher 608 to urge the rod pusher towards the first rod-receivingrecess 604 and firmly into contact with the rod R1. When the first setscrew 614 is tightened, the connector 600 can be locked to the first rodR1 to resist or prevent translation of the rod R1 with respect to theconnector along the axis A4 and to resist or prevent rotation of the rodR1 with respect to the connector about the axis A4. From a human factorsstandpoint, a user may generally associate clockwise rotation withtightening. Accordingly, the first set screw 614 can have reversethreads such that clockwise rotation of the first set screw (from theperspective of a user positioned proximal to the connector 600) movesthe first set screw proximally relative to the body 602 to tighten theconnector 600 onto the first rod R1. Alternatively, the first set screw614 can include normal threads and counterclockwise rotation can movethe first set screw proximally.

A second rod R2 can be positioned in the second rod-receiving recess 606and the second set screw 616 can be tightened to lock the rod R2 to thebody 602. In some embodiments, the second rod R2 can bear against thethird bearing surface 644C of the rod pusher 608 such that tighteningthe second rod R2 to the connector 600 exerts additional locking forceon the first rod R1.

The connector 600 can thus be used to connect a first spinal rod R1 to asecond spinal rod R2. While use of the connector 600 with first andsecond spinal rods is generally described herein, it will be appreciatedthat the connector can instead be configured for use with other types oforthopedic hardware, whether implanted or external. For example, one orboth halves of the connector 600 can be modified to couple other variouscomponents to each other (e.g., to couple a rod to a plate, to couple aplate to a plate, to couple a rod to cable, to couple a cable to acable, and so forth).

The connector 600 can provide various benefits for the user and/orpatient. For example, the biased rod pusher 608 can provide tactilefeedback when the connector 600 is “snapped” onto the first rod R1,giving the user confidence that the rod has been attached successfullybefore tightening the connector. The biased rod pusher 608 can alsoapply friction or “drag” to the rod R1 prior to locking the set screws614, 616, helping to keep the connector in place and prevent “flopping”while still allowing free movement when intended by the user. By way offurther example, the low-profile geometry of the wing portion 630 of theconnector 600 can allow the connector to be used in surgical areas wherespace is limited (e.g., in the cervical area of the spine). In anexemplary method, the wing portion 630 of the connector 600 can behooked onto a first rod R1 at a location between two bone anchors towhich the rod is coupled, the two bone anchors being implanted inadjacent vertebral levels of the cervical spine. As yet another example,the connector 600 can facilitate independent locking of the first andsecond rods R1, R2. This can allow the connector 600 to be locked to thefirst rod R1 to limit or prevent movement of the connector before thesecond rod R2 is attached and/or locked.

An exemplary method of using the connectors disclosed herein isdescribed below.

The procedure can begin by forming an open or percutaneous incision inthe patient to access a target site. The target site can be one or morevertebrae, a long bone or multiple portions of a long bone, or any otherbone or non-bone structure of the patient. As shown in FIG. 7, thetarget site can be multiple vertebrae in the patient's cervical andthoracic spine.

Bone anchors can be driven into one or more of the vertebrae and spinalrods can be attached thereto using known techniques. In the illustratedexample, bilateral spinal rods R1, R2 are coupled to four adjacentvertebrae V1-V4 using eight bone anchors S1-S8. In addition, bilateralrods R3, R4 are coupled to the next two adjacent vertebrae V5-V6 usingfour bone anchors S9-S12. The rods R1, R2 can be connected to the rodsR3, R4, respectively, using four connectors C1-C4 of the type describedherein (e.g., any of the connectors 100, 200, 300, 400, 500, 600 orcombinations or variations thereof).

As shown, the low-profile nature of the connectors C1-C4 can allow themto be installed at adjacent vertebral levels on the same rod (e.g.,between V2/V3 and between V3/V4). As also shown, the connectors C1-C4can connect to the rods R1, R2 between bone anchors installed inadjacent vertebral levels.

The connectors C1-C4 can “snap” onto the rods R1, R2, thereby providingtactile feedback to the user that the connectors are secured.

The connectors C1-C4 can “drag” against the rods R1, R2, therebyallowing for provisional positioning and retention of the connectorsprior to locking the connectors to the rods R1, R2 and/or to the rodsR3, R4.

The snap and/or drag features of the connectors C1-C4 can provideconfidence that the connector will stay in position, can make constructassembly easier, and can reduce the risk of having to retrieve droppedconnectors from vital vascular or neural structures.

The connectors C1-C4 can include independent locking features such thatthey can be locked to the rods R1, R2 prior to being locked to the rodsR3, R4 or vice versa.

The connectors C1-C4 can include single-step locking features such thatthey can be simultaneously locked to their respective rods. For example,connector C1 can be simultaneously locked to rods R1 and R3.

All of the rods R1-R4, the connectors C1-C4, and the bone anchors S1-S12can be installed in a single procedure.

Alternatively, the rods R1, R2 and the bone anchors S1-S8 may have beeninstalled in a previous procedure, and the current procedure can be arevision procedure in which the rods R3, R4, the connectors C1-C4, andthe bone anchors S9-S12 are installed to extend the previously-installedconstruct to additional levels.

The connectors C1-C4 can be attached to position the rods R1-R4 suchthat they are substantially parallel to one another and substantiallylie in a common coronal plane as shown. The connectors C1-C4 can also berotated 90 degrees from the orientation shown to position the rod pairsR1, R3 and R2, R4 such that they substantially lie in respective commonsagittal planes.

The above steps can be repeated to install additional rods and/orconnectors at the same or at different vertebral levels. Finaltightening or other adjustment of the construct can be performed and theprocedure can be completed using known techniques and the incisionclosed.

It should be noted that any ordering of method steps expressed orimplied in the description above or in the accompanying drawings is notto be construed as limiting the disclosed methods to performing thesteps in that order. Rather, the various steps of each of the methodsdisclosed herein can be performed in any of a variety of sequences. Inaddition, as the described methods are merely exemplary embodiments,various other methods that include additional steps or include fewersteps are also within the scope of the present disclosure.

While the methods illustrated and described herein generally involveattaching spinal rods to multiple vertebrae, it will be appreciated thatthe connectors and methods herein can be used with various other typesof fixation or stabilization hardware, in any bone, in non-bone tissue,or in non-living or non-tissue objects. The connectors disclosed hereincan be fully implanted, or can be used as part of an external fixationor stabilization system. The devices and methods disclosed herein can beused in minimally-invasive surgery and/or open surgery.

The devices disclosed herein and the various component parts thereof canbe constructed from any of a variety of known materials. Exemplarymaterials include those which are suitable for use in surgicalapplications, including metals such as stainless steel, titanium, oralloys thereof, polymers such as PEEK, ceramics, carbon fiber, and soforth. The various components of the devices disclosed herein can berigid or flexible. One or more components or portions of the device canbe formed from a radiopaque material to facilitate visualization underfluoroscopy and other imaging techniques, or from a radiolucent materialso as not to interfere with visualization of other structures. Exemplaryradiolucent materials include carbon fiber and high-strength polymers.

Although specific embodiments are described above, it should beunderstood that numerous changes may be made within the spirit and scopeof the concepts described.

The invention claimed is:
 1. A connector, comprising: a body thatdefines first and second rod-receiving recesses, the body havingproximal and distal ends that define a proximal-distal axis extendingtherebetween; a rod pusher slidably disposed within a tunnel formed inthe body and configured to translate with respect to the body along arod pusher axis; a first set screw threadably received in the body totranslate the rod pusher along the rod pusher axis and lock a first rodwithin the first rod-receiving recess; and a second set screw threadablyreceived in the body to lock a second rod within the secondrod-receiving recess, wherein the first and second set screws have acommon rotation axis.
 2. The connector of claim 1, further comprising abias element configured to bias the rod pusher along the rod pusher axistowards the first rod-receiving recess.
 3. The connector of claim 2,wherein the bias element is received within a through-bore formed in therod pusher.
 4. The connector of claim 2, wherein the bias elementcomprises a leaf spring received within a through-bore formed in the rodpusher and first and second recesses formed in the body.
 5. Theconnector of claim 4, wherein the first and second recesses are definedby first and second bore holes formed in a distal-facing surface of thebody.
 6. The connector of claim 4, wherein the through-bore in the rodpusher includes a reduced-width middle portion and opposed end portionshaving an increased width, the middle portion being defined at least inpart by a pin inserted through a pin hole that intersects thethrough-bore in the rod pusher.
 7. The connector of claim 1, wherein thefirst rod-receiving recess is open in a distal direction and wherein thesecond rod-receiving recess is open in a proximal direction.
 8. Theconnector of claim 1, wherein the rod pusher axis is substantiallyperpendicular to the proximal-distal axis.
 9. The connector of claim 1,wherein the first rod-receiving recess is formed in a wing portion ofthe body, the wing portion having a height dimension extending parallelto a longitudinal axis of the first rod-receiving recess, wherein theheight of the wing portion is less than about 5 mm.
 10. The connector ofclaim 1, wherein the first rod-receiving recess is formed in a wingportion of the body, the wing portion having a height dimensionextending parallel to a longitudinal axis of the first rod-receivingrecess, wherein a ratio of the height of the wing portion to a diameterof the first rod-receiving recess is less than about 2:1.
 11. Theconnector of claim 1, wherein advancing the first set screw proximallyrelative to the body causes a surface of the first set screw to bearagainst a bearing surface of the rod pusher to urge the rod pushertowards the first rod-receiving recess and to lock a first rod therein.12. The connector of claim 1, wherein a drag force is exerted on a firstrod when the first rod is disposed in the first rod-receiving recess.13. The connector of claim 1, wherein the connector provides tactilefeedback when a first rod is snapped into the first rod-receivingrecess.
 14. The connector of claim 1, wherein the common rotation axisis parallel to the proximal-distal axis.
 15. The connector of claim 1,wherein the rod pusher has a first bearing surface configured to bearagainst a first rod disposed in the first rod-receiving recess, a secondbearing surface configured to bear against the first set screw, and athird bearing surface configured to bear against a second rod disposedin the second rod-receiving recess.
 16. A connector, comprising: a bodythat defines first and second rod-receiving recesses, the body havingproximal and distal ends that define a proximal-distal axis extendingtherebetween; a rod pusher slidably disposed within a tunnel formed inthe body and configured to translate with respect to the body along arod pusher axis; a first set screw threadably received in the body totranslate the rod pusher along the rod pusher axis and lock a first rodwithin the first rod-receiving recess, and a second set screw threadablyreceived in the body to lock a second rod within the secondrod-receiving recess, wherein rotating the first set screw in a firstdirection moves the first set screw proximally to lock a first rodwithin the first rod-receiving recess and wherein rotating the secondset screw in the first direction moves the second set screw distally tolock a second rod within the second rod-receiving recess.
 17. A methodof connecting first and second spinal rods, comprising: positioning afirst spinal rod within a first rod-receiving recess formed in a bodyportion of a connector; rotating a first set screw within the body abouta rotation axis to translate a rod pusher within the body towards thefirst rod-receiving recess and thereby urge the rod pusher against thefirst spinal rod to lock the first spinal rod to the connector;positioning a second spinal rod within a second rod-receiving recessformed in the body portion of the connector; and rotating a second setscrew within the body about the rotation axis to lock the second spinalrod to the connector.
 18. The method of claim 17, wherein locking thesecond spinal rod comprises tightening a second set screw within thebody.
 19. The method of claim 17, further comprising hooking a wingportion of the connector onto the first rod at a location between twobone anchors to which the first rod is coupled, the two bone anchorsbeing implanted in adjacent vertebral levels of a patient's spine. 20.The method of claim 17, wherein positioning the first spinal rod withinthe first rod-receiving recess comprises displacing the rod pusher awayfrom the first rod-receiving recess and at least one of bending,straining, deflecting, and compressing a bias element acting on the rodpusher such that the rod pusher exerts a drag force on the first rodbefore the first set screw is tightened.
 21. The method of claim 17,wherein tightening the first set screw comprises contacting a rampedsurface of the set screw with a corresponding ramped surface of the rodpusher.
 22. The method of claim 17, wherein locking the second rodcomprises forcing the second rod against the rod pusher to force the rodpusher against the first rod.
 23. A method of connecting first andsecond spinal rods, comprising: positioning a first spinal rod within afirst rod-receiving recess formed in a body portion of a connector;tightening a first set screw within the body to translate a rod pusherwithin the body towards the first rod-receiving recess and thereby urgethe rod pusher against the first spinal rod to lock the first spinal rodto the connector; positioning a second spinal rod within a secondrod-receiving recess formed in the body portion of the connector; andlocking the second spinal rod to the connector by tightening a secondset screw within the body, wherein rotating the first set screw in afirst direction moves the first set screw proximally to lock the firstrod within the first rod-receiving recess and wherein rotating thesecond set screw in the first direction moves the second set screwdistally to lock the second rod within the second rod-receiving recess.